diff --git a/game/game.cpp b/game/game.cpp
index 2d07b9f..0389e72 100644
--- a/game/game.cpp
+++ b/game/game.cpp
@@ -8,8 +8,8 @@
 
 Game::Game()
 {
-    // advance simulation with 100 Hz
-    m_time_step = 1.0 / 100.0;
+    // advance simulation in fixed steps with 100 Hz
+    m_time_step          = 1.0 / 100.0;
     m_time_for_next_step = 0.0;
 
     m_state = new game::State();
@@ -20,23 +20,42 @@ Game::Game()
 
 bool Game::cycle(float dt)
 {
+#if 1
+    // XXX the following is just testing code to do things
+
+    static float total = 0.0;
     static float acc = 0.0;
-    acc += dt;
+
+    //if (total == 0.0) {
+    //    float speed = 0.005;
+    //    m_state->players[0]->addCommand(new game::SetSpeedCommand(speed));
+    //    for (int i=0; i<100; i++) {
+    //        float a = 2.0 * M_PI * util::randf_0_1();
+    //        m_state->players[0]->addCommand(new game::ShootCommand(a));
+    //    }
+    //}
+
+    acc   += dt;
+    total += dt;
 
     float spawnInterval = 0.1;
     while(acc > spawnInterval) {
         acc -= spawnInterval;
 
-        float a = 2.0 * M_PI * util::randf_0_1();
+        float angle = 2.0 * M_PI * util::randf_0_1();
         float speed = 0.005;
-        m_state->players[0]->addCommand(new game::ShootCommand(a, speed));
-    }
 
-#if 1
-    if (dt >= 10.0) {
-        //std::cout<<"time to big: " << dt << std::endl;
-        dt = m_time_step;
+        m_state->players[0]->addCommand(new game::SetSpeedCommand(speed));
+        m_state->players[0]->addCommand(new game::ShootCommand(angle));
+
+        //static bool done = false;
+        //if (total >= 10.0 && !done) {
+        //    done = true;
+
+        //    m_state->players[0]->addCommand(new game::ClearTracesCommand());
+        //}
     }
+#endif
 
     //std::cout<<"adding dt: " << dt << std::endl;
     m_time_for_next_step += dt;
@@ -53,11 +72,4 @@ bool Game::cycle(float dt)
     //std::cout << m_time_for_next_step << " s remaining time, " << steps << " steps taken." << std::endl;
 
     return true;
-#else
-    (void) dt;
-
-    m_state->advance(dt);
-
-    return true;
-#endif
 }
diff --git a/game/game_window.hpp b/game/game_window.hpp
index 02c1aa0..884a628 100644
--- a/game/game_window.hpp
+++ b/game/game_window.hpp
@@ -11,6 +11,7 @@
 #include "state/player.hpp"
 #include "state/planet.hpp"
 #include "state/ship.hpp"
+#include "state/explosion.hpp"
 
 class GameWindow : public endofthejedi::GLWindow {
 private:
@@ -46,7 +47,11 @@ protected:
             drawTrace(trace);
         }
 
-        for (const game::Ship *ship : m_game->state()->ships) {
+        for (const game::Explosion *explosion : m_game.state()->explosions) {
+            drawExplosion(explosion);
+        }
+
+        for (const game::Ship *ship : m_game.state()->ships) {
             drawShip(ship->position);
         }
 
@@ -78,7 +83,6 @@ protected:
     }
 
     void drawMissile(const glm::vec2 &pos)
-
     {
         glm::vec3 color = glm::vec3(1.0, 1.0, 0.3);
         m_renderer.drawCircle(pos.x, pos.y, 0.01, color.x, color.y, color.z, 6);
@@ -92,6 +96,17 @@ protected:
         }
     }
 
+    void drawExplosion(const game::Explosion *explosion)
+    {
+        // TODO: transparent
+        // TODO: with glow in the middle
+        float r = explosion->maxRadius * (explosion->age / explosion->maxAge);
+
+        // TODO: transparency?
+        glm::vec3 color = glm::vec3(1.0, 0.9, 0.1);
+        m_renderer.drawCircle(explosion->position.x, explosion->position.y, r, color.x, color.y, color.z, 64);
+    }
+
 public:
     GameWindow(unsigned int width, unsigned int height, Game* game)
         : endofthejedi::GLWindow(width, height) { m_game = game; }
diff --git a/game/state/commands.cpp b/game/state/commands.cpp
index b84a214..1a64d89 100644
--- a/game/state/commands.cpp
+++ b/game/state/commands.cpp
@@ -2,6 +2,8 @@
 
 #include "trace.hpp"
 
+#include <iostream>
+
 namespace game {
     void ShootCommand::apply(Player *player, State *state) const
     {
@@ -10,23 +12,72 @@ namespace game {
         // TODO: idea
         // shoot multiple rockets at once or from different positions after
         // level up / upgrade ...
-        Missile *missile = new Missile(player, player->ship->position, m_angle, m_speed);
+        Missile *missile = new Missile(player, player->ship->position, m_angle, player->speed);
 
         Trace *trace = new Trace(missile);
         missile->trace = trace;
 
-        player->energy -= m_speed;
+        player->energy -= player->speed;
         player->missiles.push_back(missile);
 
         state->addTrace(trace);
     }
 
-    bool ShootCommand::allowed(const Player *player, const State *state) const
+    bool ShootCommand::ready(const Player *player, const State *state) const
     {
         (void) state;
 
         // TODO
-        return player->alive && player->energy >= m_speed;
+        return player->alive && player->energy >= player->speed;
         //return player->alive;
     }
+
+    void ChangeNameCommand::apply(Player *player, State *state) const
+    {
+        // discard if not unique
+        for (const Player *other : state->players) {
+            if (m_name == other->name) {
+                std::cout << "name '" << m_name << "' already given to player #" << other->id << std::endl;
+                return;
+            }
+        }
+
+        player->name = m_name;
+    }
+
+    void SetSpeedCommand::apply(Player *player, State *state) const
+    {
+        (void) state;
+        player->speed = m_speed;
+    }
+
+    void ClearTracesCommand::apply(Player *player, State *state) const
+    {
+        std::cout<<"clearing traces!!!" << std::endl;
+
+        size_t i = 0;
+        while(i < state->traces.size()) {
+            Trace *trace = state->traces[i];
+            if (trace->missile == nullptr && trace->player == player) {
+                state->deleteTrace(i);
+
+            } else {
+                i++;
+            }
+        }
+    }
+
+#if 0
+    bool TakeOverPlayerCommand::ready(const Player *player, const State *state) const
+    {
+        (void) state;
+        return state->havePlayerGrantFor(player->id, m_otherPlayerId);
+    }
+
+    void TakeOverPlayerCommand::apply(Player *player, State *state) const
+    {
+        if (
+        state->playerGrant(player->id, m_otherPlayerId);
+    }
+#endif
 }
diff --git a/game/state/commands.hpp b/game/state/commands.hpp
index 5c8ff97..dd88c0c 100644
--- a/game/state/commands.hpp
+++ b/game/state/commands.hpp
@@ -9,6 +9,10 @@
 #include <iostream>
 
 namespace game {
+    /**
+     * Base class for commands.
+     * must derive from this.
+     */
     class Command {
     public:
         Command()
@@ -19,7 +23,11 @@ namespace game {
         {
         }
 
-        virtual bool allowed(const Player *player, const State *state) const
+        // check whether the command is ready to execute.
+        // if not, wait.
+        // note: stuff like for admin should be done in execute() to discard the
+        // command and not block the queue.
+        virtual bool ready(const Player *player, const State *state) const
         {
             (void) player;
             (void) state;
@@ -38,19 +46,95 @@ namespace game {
         virtual std::string name() const { return "<unnamed>"; }
     };
 
+    /**********************************************************************/
+    /* Implemented commands */
+    /**********************************************************************/
+
+    /*
+     * Shoot at angle and optional speed.
+     * TODO
+     */
     class ShootCommand : public Command {
     public:
-        ShootCommand(float angle, float speed) : m_angle(angle), m_speed(speed)
+        ShootCommand(float angle) : m_angle(angle)
         {
         }
 
         std::string name() const { return "<shoot>"; }
 
-        void apply(        Player *player,       State *state) const;
-        bool allowed(const Player *player, const State *state) const;
+        void apply(      Player *player,       State *state) const;
+        bool ready(const Player *player, const State *state) const;
 
     private:
         float m_angle;
+    };
+
+    /**
+     * Change the name of the player if it will be uniuqe.
+     */
+    class ChangeNameCommand : public Command {
+    public:
+        ChangeNameCommand(const std::string &name) : m_name(name)
+        {
+        }
+
+        std::string name() const { return "<change name>"; }
+
+        void apply(Player *player, State *state) const;
+
+    private:
+        std::string m_name;
+    };
+
+    /**
+     * clear all traces of this player that are done
+     */
+    class ClearTracesCommand : public Command {
+    public:
+        ClearTracesCommand()
+        {
+        }
+
+        std::string name() const { return "<clear traces>"; }
+
+        void apply(Player *player, State *state) const;
+    };
+
+    /**
+     * Set default speed of next shots for this player.
+     */
+    class SetSpeedCommand : public Command {
+    public:
+        SetSpeedCommand(float speed) : m_speed(speed)
+        {
+        }
+
+        std::string name() const { return "<set speed>"; }
+
+        void apply(Player *player, State *state) const;
+
+    private:
         float m_speed;
     };
+
+#if 0
+    /**
+     * Take over a session for a player that left.
+     * An admin must confirm this command.
+     */
+    class TakeOverPlayerCommand : public Command {
+    public:
+        TakeOverPlayerCommand(int otherPlayerId) : m_otherPlayerId(otherPlayerId)
+        {
+        }
+
+        std::string name() const { return "<take over player>"; }
+
+        void apply(      Player *player,       State *state) const;
+        bool ready(const Player *player, const State *state) const;
+
+    private:
+        int m_otherPlayerId;
+    };
+#endif
 }
diff --git a/game/state/explosion.hpp b/game/state/explosion.hpp
index 66c234f..32169eb 100644
--- a/game/state/explosion.hpp
+++ b/game/state/explosion.hpp
@@ -2,31 +2,32 @@
 
 #include <glm/vec2.hpp>
 
+#include "util.hpp"
+
+#include "missile_hit_type.hpp"
+
 namespace game {
     /**
      * Explosion: just an effect which looks good.
      */
     class Explosion {
     public:
-        enum class Kind {
-            MissileExplodesInSpace, // missile explode in free space
-            MissileAgainstPlanet,   // explosion of missile when it hits a planet
-            MissileAgainstShip      // bigger explosion: missile hits a ship which explodes with it
-        };
-
-        Explosion(const glm::vec2 &pos, Kind kind, float maxAge=1.0)
-            : position(pos), kind(kind), age(0.0), maxAge(maxAge)
+        Explosion(const glm::vec2 &pos, Hit hit, float maxAge=1.0)
+            : hit(hit)
+            , position(pos)
+            , age(0.0)
+            , maxAge(maxAge * (1.0 + 0.1*util::randf_0_1()))
+            , maxRadius(0.05)
         {
         }
 
-        const Kind      kind;     // kind of the explosion
+        const Hit       hit;      // kind of the explosion depends on the hit type
         const glm::vec2 position; // position where it starts
         float           age;      // age (in seconsd) of the explosion
 
         // age (in seconds) when the explosion is not visible
         // anymore and will disappear afterwards
         const float     maxAge;
+        const float     maxRadius; // current radius depends on time.
     };
 }
-
-#endif
diff --git a/game/state/missile.cpp b/game/state/missile.cpp
index b789b5f..cbc3e58 100644
--- a/game/state/missile.cpp
+++ b/game/state/missile.cpp
@@ -49,7 +49,7 @@ namespace game {
             if (dist <= planet->radius) {
                 // TODO: collect all hits and return the first one only
                 // TODO: find exact hit position!
-                return Missile::Event(position, Missile::HitObject::HitPlanet);
+                return Missile::Event(position, planet->id);
             }
 
             dist *= 20.0;
@@ -77,7 +77,7 @@ namespace game {
         // check if distance to center of the universe is getting too big
         float distToCenter = glm::length(position);
         if (distToCenter > state->maxMissileDistance()) {
-            return Missile::Event(position, Missile::HitObject::LeftUniverse);
+            return Missile::Event(position, Hit::BorderOfUniverse);
         }
 
         return Missile::Event(position);
diff --git a/game/state/missile.hpp b/game/state/missile.hpp
index c68706d..c7aa1df 100644
--- a/game/state/missile.hpp
+++ b/game/state/missile.hpp
@@ -3,6 +3,8 @@
 #include <glm/vec2.hpp>
 #include <glm/vec3.hpp>
 
+#include "missile_hit_type.hpp"
+
 namespace game {
     class State;
     class Ship;
@@ -15,39 +17,42 @@ namespace game {
     // trace then belongs to the player.
     class Missile {
     public:
-        enum class HitObject {
-            Nothing,
-            HitPlayer,
-            HitPlanet,
-            // HitMissile,
-            LeftUniverse
-        };
 
         // missile advances to pos. if hit != Nothing, it hits something and
         // stops existing afterwards.
         class Event {
         public:
-            Event(const glm::vec2 &pos) : Event(pos, HitObject::Nothing)
+            Event(const glm::vec2 &pos)
+                : Event(pos, Hit::Nothing)
             {
             }
 
-            Event(const glm::vec2 &pos, HitObject hit)
-                : hit(hit), pos(pos)
+            Event(const glm::vec2 &pos, Hit hit)
+                : hit(hit), position(pos)
             {
             }
 
+            Event(const glm::vec2 &pos, int planetId) : Event(pos, Hit::Planet)
+            {
+                this->planetId = planetId;
+            }
+
             Event(const glm::vec2 &pos, int playerIdKiller, int playerIdVictim)
-                : Event(pos, HitObject::HitPlayer)
+                : Event(pos, Hit::Ship)
             {
                   this->playerIdKiller = playerIdKiller;
                   this->playerIdVictim = playerIdVictim;
             }
 
-            HitObject hit;
-            glm::vec2 pos;
+            Hit       hit;
+            glm::vec2 position;
 
+            // if a player was hit, these are valid.
             int playerIdKiller;
             int playerIdVictim;
+
+            // if a planet was hit, this is valid
+            int planetId;
         };
 
         Missile(Player *player, const glm::vec2 &pos, float angle, float speed);
diff --git a/game/state/missile_hit_type.hpp b/game/state/missile_hit_type.hpp
new file mode 100644
index 0000000..04f1af3
--- /dev/null
+++ b/game/state/missile_hit_type.hpp
@@ -0,0 +1,19 @@
+#pragma once
+
+namespace game {
+    /*
+     * A missile can hit different objects the type says which one.
+     * Used in various places so extra file for this.
+     */
+    enum class Hit {
+        Nothing,
+        Ship,
+        Planet,
+
+        // TODO could be needed for really fancy explosions because
+        // this is cool and should noh happen very often
+        // AgainstMissile,
+
+        BorderOfUniverse
+    };
+}
diff --git a/game/state/planet.hpp b/game/state/planet.hpp
index 0407683..e6ff6e7 100644
--- a/game/state/planet.hpp
+++ b/game/state/planet.hpp
@@ -2,11 +2,39 @@
 
 #include "object.hpp"
 
+#include <cstdlib>
+
 namespace game {
     class Planet : public Object {
     public:
-        Planet(const glm::vec2 &pos, float r) : Object(pos, r)
+        /**
+         * Planets are build out of one material.
+         * TODO: support mixture or multiple material per planet.
+         */
+        enum class Material {
+            Rock,
+            Metal,
+            Sand,
+            Gas,
+            Ice,
+            Water,
+            Sun
+        };
+
+        Planet(const glm::vec2 &pos, int id, float r) : Planet(pos, id, r, Material::Rock)
         {
         }
+
+        Planet(const glm::vec2 &pos, int id, float r, Material mat)
+            : Object(pos, r)
+            , id(id)
+            , material(mat)
+            , seed(rand())
+        {
+        }
+
+        int      id;
+        Material material; // for rendering and physics (can fly through sun and outer gas planets)
+        int      seed;     // just for rendering variation
     };
 }
diff --git a/game/state/player.hpp b/game/state/player.hpp
index 199a411..3a6aeb4 100644
--- a/game/state/player.hpp
+++ b/game/state/player.hpp
@@ -1,5 +1,6 @@
 #pragma once
 
+#include <string>
 #include <deque>
 #include <vector>
 
@@ -15,12 +16,14 @@ namespace game {
     public:
         int        id;
         bool       alive;
+        float      speed;
         float      energy;
         float      deadTimeCounter;
         Ship      *ship;
+        std::string name;
         std::vector<Missile*> missiles;
 
-        Player(int id) : id(id), alive(true), energy(0.0), ship(nullptr)
+        Player(int id) : id(id), alive(true), speed(0.01), energy(0.0), ship(nullptr), name("<unnamed>")
         {
         }
 
diff --git a/game/state/state.cpp b/game/state/state.cpp
index acc2502..63ef686 100644
--- a/game/state/state.cpp
+++ b/game/state/state.cpp
@@ -6,6 +6,7 @@
 #include <glm/vec3.hpp>
 #include <glm/gtx/norm.hpp>
 
+#include "missile_hit_type.hpp"
 #include "object.hpp"
 #include "missile.hpp"
 #include "player.hpp"
@@ -13,6 +14,7 @@
 #include "ship.hpp"
 #include "commands.hpp"
 #include "trace.hpp"
+#include "explosion.hpp"
 
 #include "util.hpp"
 
@@ -23,6 +25,7 @@ namespace game {
         m_maxMissileDistance = 2.0;
         m_playerRespawnTime  = 2.0;
         m_defaultEnergy      = 10.0;
+        m_maxNumTraces       = 10;
 
         bool planetsOnCircle = false;
 
@@ -43,7 +46,7 @@ namespace game {
                 }
             } while(glm::length(pos) < 0.2 && tries++ < 1000);
 
-            planets.push_back(new Planet(pos, 0.03 + 0.07*util::randf_0_1()));
+            planets.push_back(new Planet(pos, i, 0.03 + 0.07*util::randf_0_1()));
         }
     }
 
@@ -108,7 +111,7 @@ namespace game {
             // try to execute as much queued commands as possible.
             while (player->hasCommandInQueue()) {
                 Command *command = player->peekCommand();
-                if (!command->allowed(player, this)) {
+                if (!command->ready(player, this)) {
                     break;
                 }
 
@@ -145,12 +148,9 @@ namespace game {
 
         // TODO
         // add points
-        //
+
         // TODO
         // message
-        //
-        // TODO
-        // respawn timer
     }
 
     void State::advancePlayerMissiles(float dt)
@@ -164,26 +164,27 @@ namespace game {
                 //std::cout<<"missile: " << (long unsigned int) missile << std::endl;
                 const Missile::Event evt = missile->advance(this, dt);
 
-                missile->trace->addPointFromMissile();
+                const bool isHit = (evt.hit != Hit::Nothing);
 
-                // TODO:
-                // spawn just if the path differs
+                if (missile->trace != nullptr) {
+                    missile->trace->addPointFromMissile(isHit); // force point if missile gets destroyed a
+                }
 
-                if (evt.hit == Missile::HitObject::Nothing) {
+                if (!isHit) {
                     i++;
 
                 } else {
                     switch(evt.hit) {
-                        case Missile::HitObject::HitPlanet:
+                        case Hit::Planet:
                             //std::cout<<"hit Planet" << std::endl;
                             break;
 
-                        case Missile::HitObject::HitPlayer:
+                        case Hit::Ship:
                             //std::cout<<"hit Player" << std::endl;
                             playerKillsPlayer(playerForId(evt.playerIdKiller), playerForId(evt.playerIdVictim));
                             break;
 
-                        case Missile::HitObject::LeftUniverse:
+                        case Hit::BorderOfUniverse:
                             //std::cout<<"missile left the universe." << std::endl;
                             break;
 
@@ -191,6 +192,12 @@ namespace game {
                             break;
                     }
 
+                    addExplosionFromHit(&evt);
+
+                    if (missile->trace != nullptr) {
+                        missile->trace->finish();
+                    }
+
                     player->missiles.erase(player->missiles.begin() + i);
                     delete(missile);
                     //std::cout<<std::endl;
@@ -202,16 +209,32 @@ namespace game {
         }
     }
 
+    void State::advanceExplosions(float dt)
+    {
+        size_t i=0;
+        while(i < explosions.size()) {
+            Explosion *explosion = explosions[i];
+            explosion->age += dt;
+            if (explosion->age >= explosion->maxAge) {
+                delete(explosion);
+                explosions.erase(explosions.begin()+i);
+                continue;
+            }
+
+            i++;
+        }
+    }
+
     void State::advance(float dt)
     {
-        //std::cout<<"advance ship spawns" << std::endl;
         advancePlayerShipSpawns(dt);
 
-        //std::cout<<"advance commands" << std::endl;
+        advanceExplosions(dt);
+
         advancePlayerCommands(dt);
 
-        //std::cout<<"advance missiles" << std::endl;
         advancePlayerMissiles(dt);
+
     }
 
     Player *State::playerForId(int playerId)
@@ -270,6 +293,56 @@ namespace game {
 
     void State::addTrace(Trace *trace)
     {
+        //int count = 0;
+        //for (Trace *old : traces) {
+        //    if (old->playerId == trace->playerId) {
+        //        count++;
+        //    }
+        //}
+
+        //if (count > m_maxNumTraces) {
+        //}
+
         traces.push_back(trace);
     }
+
+    void State::deleteTrace(size_t index)
+    {
+        if (index >= traces.size()) {
+            std::cerr << "can't find trace with invalid index " << index << std::endl;
+            return;
+        }
+
+        Trace *trace = traces[index];
+
+        //std::cout<<"removing a trace" << std::endl;
+        if (trace->missile != nullptr) {
+            // delete backlink.
+            // XXX: there's a missile without a trace now.
+            trace->missile->trace = nullptr;
+        }
+
+        traces.erase(traces.begin() + index);
+        delete(trace);
+    }
+
+    void State::deleteTrace(Trace *trace)
+    {
+        size_t i = 0;
+        while(i < traces.size()) {
+            if (traces[i] == trace) {
+                deleteTrace(i);
+                break;
+            }
+        }
+    }
+
+    void State::addExplosionFromHit(const Missile::Event *evt)
+    {
+        if (evt->hit == Hit::Nothing || evt->hit == Hit::BorderOfUniverse) {
+            return;
+        }
+
+        explosions.push_back(new Explosion(evt->position, evt->hit));
+    }
 }
diff --git a/game/state/state.hpp b/game/state/state.hpp
index a526d06..40c71f6 100644
--- a/game/state/state.hpp
+++ b/game/state/state.hpp
@@ -7,14 +7,28 @@
 
 #include <glm/vec2.hpp>
 
+#include "missile.hpp"
+
+// TODO:
+// give points for equipment / better weapons / more energy when:
+// - player discovers the universe
+//
+// - the shot which made a kill was much longer than the direkt line between
+//   player and his target
+//
+// - add wormholes
+// - add blackholes
+// - shoot through suns which add a fire mantle to the rocket to make it more
+//   thick and dangerous but it gets destroyed after some time.
+
 namespace game {
     // forward declarations
     class Command;
-    class Missile;
     class Player;
     class Planet;
     class Ship;
     class Trace;
+    class Explosion;
 
     class State {
     public:
@@ -55,16 +69,21 @@ namespace game {
         // add a trace to the list of traces.
         void addTrace(Trace *trace);
 
+        // delete traces with this command
+        void deleteTrace(Trace *trace); // using a pointer
+        void deleteTrace(size_t index); // using an index
+
         /*************************************************************************/
         /* Rendering */
         /*************************************************************************/
 
         // Game items which should be rendered are here:
         // (access missiles by iterating over player's missiles attribute)
-        std::vector<Planet*>  planets;
-        std::vector<Ship*>    ships;
-        std::vector<Player*>  players;
-        std::vector<Trace*>   traces;
+        std::vector<Planet*>    planets;
+        std::vector<Ship*>      ships;
+        std::vector<Player*>    players;
+        std::vector<Trace*>     traces;
+        std::vector<Explosion*> explosions;
 
     private:
         /*************************************************************************/
@@ -73,6 +92,9 @@ namespace game {
 
         void playerKillsPlayer(Player *killer, Player *victim);
 
+        void addExplosionFromHit(const Missile::Event *evt);
+
+        void advanceExplosions(float dt);
         void advancePlayerShipSpawns(float dt);
         void advancePlayerCommands(float dt);
         void advancePlayerMissiles(float dt);
@@ -90,5 +112,6 @@ namespace game {
         float m_shipRadius;
         float m_defaultEnergy;
         int m_nextId=0;
+        int   m_maxNumTraces;
     };
 };
diff --git a/game/state/trace.cpp b/game/state/trace.cpp
index 4d93d2c..0b51695 100644
--- a/game/state/trace.cpp
+++ b/game/state/trace.cpp
@@ -4,6 +4,8 @@
 
 #include "missile.hpp"
 
+#include <iostream>
+
 namespace game {
     Trace::TracePoint::TracePoint(const Missile *missile)
         : position(missile->position)
@@ -11,7 +13,16 @@ namespace game {
     {
     }
 
-    Trace::Trace(const Missile *missile) : missile(missile), fidelityCounter(0)
+    Trace::~Trace()
+    {
+        //std::cout<<"~Trace()" << std::endl;
+    }
+
+    Trace::Trace(Missile *missile)
+        : missile(missile)
+        , player(missile->player)
+        , fidelityCounter(0)
+        , age(0.0)
     {
         points.push_back(TracePoint(missile));
     }
@@ -24,4 +35,10 @@ namespace game {
             points.push_back(TracePoint(missile));
         }
     }
+
+    void Trace::finish()
+    {
+        //std::cout<<"trace finished now!" << std::endl;
+        missile = nullptr;
+    }
 }
diff --git a/game/state/trace.hpp b/game/state/trace.hpp
index ab33b2f..2b4f4f0 100644
--- a/game/state/trace.hpp
+++ b/game/state/trace.hpp
@@ -5,6 +5,7 @@
 
 namespace game {
     class Missile;
+    class Player;
 
     /*
      * Trace of a missile through the space.
@@ -12,7 +13,8 @@ namespace game {
      */
     class Trace {
         public:
-            Trace(const Missile *missile);
+            Trace(Missile *missile);
+            ~Trace();
 
             // Add the current position of the missile as a new point on the
             // trace.
@@ -21,6 +23,10 @@ namespace game {
             // the missile) in case the fidelityCounter would skip the current position.
             void addPointFromMissile(bool forceAdd=false);
 
+            // call this to mark the trace as finish and disconnect it from the
+            // missile.
+            void finish();
+
             // TODO: add extendLastPointToPosition() method for saving points /
             // optimization later on
 
@@ -35,11 +41,16 @@ namespace game {
             };
 
             std::vector<TracePoint> points;
-            const Missile *missile; // missile which creates this path.
+            Missile                *missile; // missile which creates this path.
+            Player                 *player;
 
             // counter which is incremented each time addPointFromMissile() is called.
             // when reaching a certain value the point is saved for
             // optimization.
             int fidelityCounter;
+
+            // age of the trace. if too old, it can be removed to save
+            // space/power
+            float age;
     };
 }