diff --git a/agent.cc b/agent.cc
index 2ed30bb..eef806b 100644
--- a/agent.cc
+++ b/agent.cc
@@ -8,8 +8,9 @@
 #include "map.h"
 
 void
-agent::put_at(class tile &t)
+agent::spawn_at(class tile &t)
 {
+	tile = &t;
 	if (!t.on_agent_enter(*this)) {
 		std::cerr << "Collision.";
 		exit(EXIT_FAILURE);
@@ -19,7 +20,7 @@ agent::put_at(class tile &t)
 bool
 agent::move_dir(int dir_x, int dir_y)
 {
-	if (dead)
+	if (dead || !tile)
 		return false;
 
 	chenergy(world::move_cost);
@@ -48,7 +49,7 @@ agent::move_dir(int dir_x, int dir_y)
 bool
 agent::attack_dir(int dir_x, int dir_y)
 {
-	if (dead)
+	if (dead || !tile)
 		return false;
 
 	class tile *t2 = &tile->tile_in_dir(dir_x, dir_y);
@@ -112,7 +113,7 @@ agent::on_tick(void)
 void
 agent::on_senses_update(void)
 {
-	if (!conn)
+	if (!conn || !tile)
 		return;
 
 	conn->senses(tick_id, *this);
@@ -120,7 +121,8 @@ agent::on_senses_update(void)
 
 agent::~agent()
 {
-	tile->on_agent_leave(*this);
+	if (tile)
+		tile->on_agent_leave(*this);
 	if (conn) {
 		conn->cancel();
 		conn = NULL;
diff --git a/agent.h b/agent.h
index 748c956..f5e2e01 100644
--- a/agent.h
+++ b/agent.h
@@ -16,13 +16,13 @@ public:
 	int energy;
 	bool dead;
 
-	agent(int id_, class tile &tile_, class connection *conn_)
-	: id (id_), conn (conn_), tile (&tile_)
+	agent(int id_, class connection *conn_)
+	: id (id_), conn (conn_)
 	{
-		put_at(tile_);
 		energy = world::newborn_energy;
 		dead = false;
 	};
+	void spawn_at(class tile &tile);
 
 	bool move_dir(int dir_x, int dir_y);
 	bool attack_dir(int dir_x, int dir_y);
@@ -35,10 +35,6 @@ public:
 	void on_senses_update(void);
 
 	~agent();
-
-private:
-	/* Just for initial placement. */
-	void put_at(class tile &tile);
 };
 
 #endif
diff --git a/main.cc b/main.cc
index 2d02d25..6fbff3b 100644
--- a/main.cc
+++ b/main.cc
@@ -67,7 +67,9 @@ next_agent:
 		int cfd = accept(lfd, NULL, NULL);
 		if (cfd >= 0) {
 			class connection *conn = new class connection(cfd);
-			agents.push_back(new class agent(aid++, map.agent_startpos(), conn));
+			class agent *a = new class agent(aid++, conn);
+			agents.push_back(a);
+			a->spawn_at(map.agent_startpos());
 		}
 
 		/* Collect and take actions. */