diff --git a/game/commands.odin b/game/commands.odin
index 7cd70fe..9869ce3 100644
--- a/game/commands.odin
+++ b/game/commands.odin
@@ -5,7 +5,7 @@ import rl "vendor:raylib"
 Command_Kind :: enum {
 	None,
 	Place_Tower,
-	Spawn_Test,
+	Start_Wave,
 }
 
 Command :: struct {
@@ -15,14 +15,20 @@ Command :: struct {
 }
 
 gather_commands :: proc(world: ^World) -> Command {
-	if rl.IsMouseButtonPressed(.LEFT) {
+	if world.phase == .Build && rl.IsKeyPressed(.N) {
+		return Command{kind = .Start_Wave}
+	}
+
+	if world.phase == .Build && rl.IsMouseButtonPressed(.LEFT) {
 		mouse := rl.GetMousePosition()
 		gx, gy := screen_to_grid(mouse.x, mouse.y)
 		return Command{kind = .Place_Tower, gx = gx, gy = gy}
 	}
 
-	if rl.IsKeyPressed(.SPACE) {
-		return Command{kind = .Spawn_Test}
+	if rl.IsMouseButtonPressed(.LEFT) {
+		mouse := rl.GetMousePosition()
+		gx, gy := screen_to_grid(mouse.x, mouse.y)
+		return Command{kind = .Place_Tower, gx = gx, gy = gy}
 	}
 
 	return Command{kind = .None}
@@ -31,10 +37,10 @@ gather_commands :: proc(world: ^World) -> Command {
 execute_command :: proc(world: ^World, cmd: Command) {
 	switch cmd.kind {
 	case .None:
-	case .Spawn_Test:
-		spawn_group(world, 3)
 	case .Place_Tower:
 		try_place_tower(world, cmd.gx, cmd.gy, .Archer)
+	case .Start_Wave:
+		start_wave(world)
 	}
 }
 
diff --git a/game/constants.odin b/game/constants.odin
index 2a85e20..73dfcf8 100644
--- a/game/constants.odin
+++ b/game/constants.odin
@@ -1,7 +1,7 @@
 package game
 
-MAP_W :: 16 // map width in tiles
-MAP_H :: 12 // map height in tiles
+MAP_W :: 30 // map width in tiles
+MAP_H :: 20 // map height in tiles
 TILE_SIZE :: 32 // size of tiles in pixels
 
 SCREEN_W :: MAP_W * TILE_SIZE
diff --git a/game/events.odin b/game/events.odin
index c5f4481..b71b397 100644
--- a/game/events.odin
+++ b/game/events.odin
@@ -2,6 +2,7 @@ package game
 
 Event_Kind :: enum {
 	Enemy_Killed,
+	Wave_Survived,
 }
 
 Event :: struct {
@@ -18,6 +19,8 @@ process_events :: proc(world: ^World) {
 		switch ev.kind {
 		case .Enemy_Killed:
 			world.gold += ev.gold_reward
+		case .Wave_Survived:
+			world.gold += ev.gold_reward
 		}
 	}
 	clear(&world.events)
diff --git a/game/map.odin b/game/map.odin
index ed80429..969aba0 100644
--- a/game/map.odin
+++ b/game/map.odin
@@ -31,16 +31,16 @@ init_map :: proc(world_map: ^Map) {
 		}
 	}
 
-	for x in 1 ..< 13 {
-		world_map.tiles[6][x] = .Path
+	for x in 9 ..< 21 {
+		world_map.tiles[10][x] = .Path
 	}
 
-	for y in 7 ..< 8 {
-		world_map.tiles[y][12] = .Path
+	for y in 11 ..< 14 {
+		world_map.tiles[y][20] = .Path
 	}
 
-	for y in 4 ..< 9 {
-		for x in 3 ..< 12 {
+	for y in 7 ..< 15 {
+		for x in 6 ..< 24 {
 			if world_map.tiles[y][x] != .Path {
 				world_map.tiles[y][x] = .Build
 			}
diff --git a/game/render.odin b/game/render.odin
index 0a11d2a..90d36c6 100644
--- a/game/render.odin
+++ b/game/render.odin
@@ -35,8 +35,17 @@ render_world :: proc(world: ^World) {
 	if (world.base_health == 0) {
 		rl.DrawText("**GAME OVER**", 20, 20, 20, rl.RED)
 	}
-	rl.DrawText(fmt.ctprintf("Gold: %d", world.gold), 10, 10, 20, rl.BLACK) // Gold HUD
-	rl.DrawText(fmt.ctprintf("Base HP: %d", world.base_health), 10, 32, 20, rl.BLACK) // HP HUD
-	rl.DrawText(fmt.ctprintf("Enemies: %d", active_enemy_count(world)), 10, 54, 18, rl.DARKGRAY)
+
+	rl.DrawText(fmt.ctprintf("Gold: %d", world.gold), 10, 10, 22, rl.BLACK) // Gold HUD
+	rl.DrawText(fmt.ctprintf("Base HP: %d", world.base_health), 10, 32, 22, rl.BLACK) // HP HUD
+	rl.DrawText(fmt.ctprintf("Enemies: %d", active_enemy_count(world)), 10, 54, 22, rl.BLACK)
+	rl.DrawText(fmt.ctprintf("Wave: %d / %d", world.wave, MAX_WAVES), 10, 76, 22, rl.BLACK)
+
+	switch world.phase {
+	case .Build:
+		rl.DrawText("Build - click towers, N = start wave", 10, 98, 22, rl.BLACK)
+	case .Combat:
+		rl.DrawText("Combat!", 10, 74, 22, rl.MAROON)
+	}
 }
 
diff --git a/game/tower.odin b/game/tower.odin
index 02ecc1d..701ae47 100644
--- a/game/tower.odin
+++ b/game/tower.odin
@@ -19,7 +19,7 @@ Tower_Archetype :: struct {
 }
 
 TOWER_ARCHETYPES: [Tower_Kind]Tower_Archetype = {
-	.Archer = {kind = .Archer, range = 95, damage = 12, fire_rate = 0.45, cost = TOWER_COST},
+	.Archer = {kind = .Archer, range = 20, damage = 12, fire_rate = 0.45, cost = TOWER_COST},
 }
 
 get_archetype :: proc(kind: Tower_Kind) -> Tower_Archetype {
@@ -27,6 +27,7 @@ get_archetype :: proc(kind: Tower_Kind) -> Tower_Archetype {
 }
 
 try_place_tower :: proc(world: ^World, gx, gy: int, kind: Tower_Kind) -> bool {
+	if world.phase != .Build do return false
 	arch := get_archetype(kind)
 	if !can_build_at(&world.world_map, gx, gy) do return false
 	if world.gold < TOWER_COST do return false
diff --git a/game/wave.odin b/game/wave.odin
new file mode 100644
index 0000000..a929bc3
--- /dev/null
+++ b/game/wave.odin
@@ -0,0 +1,51 @@
+package game
+
+Game_Phase :: enum {
+	Build,
+	Combat,
+}
+
+Wave_Spawner :: struct {
+	enemies_to_spawn: int,
+	spawn_timer:      f32,
+	spawn_interval:   f32,
+}
+
+start_wave :: proc(world: ^World) {
+	if world.phase != .Build do return
+	world.wave += 1
+	world.phase = .Combat
+	world.spawner = Wave_Spawner {
+		enemies_to_spawn = 5 + world.wave * 2,
+		spawn_timer      = 0,
+		spawn_interval   = 0.55,
+	}
+}
+
+update_wave :: proc(world: ^World, dt: f32) {
+	if world.phase != .Combat do return
+	if world.spawner.enemies_to_spawn <= 0 do return
+	if len(world.path) < 2 do return
+
+	world.spawner.spawn_timer -= dt
+	if world.spawner.spawn_timer <= 0 {
+		health := 15 + world.wave * 5
+		speed := 55 + f32(world.wave) * 5
+		spawn_enemy(world, health, speed)
+		world.spawner.enemies_to_spawn -= 1
+		world.spawner.spawn_timer = world.spawner.spawn_interval
+	}
+}
+
+wave_clear :: proc(world: ^World) -> bool {
+	if world.spawner.enemies_to_spawn > 0 do return false
+	return active_enemy_count(world) == 0
+}
+
+update_phase :: proc(world: ^World) {
+	if world.phase == .Combat && wave_clear(world) {
+		world.phase = .Build
+		push_event(world, .Wave_Survived, gold_reward = 25)
+	}
+}
+
diff --git a/game/world.odin b/game/world.odin
index 9d2b5e8..6339cac 100644
--- a/game/world.odin
+++ b/game/world.odin
@@ -10,12 +10,16 @@ World :: struct {
 	enemies:     [MAX_ENEMIES]Enemy,
 	towers:      [dynamic]Tower,
 	events:      [dynamic]Event,
+	phase:       Game_Phase,
+	wave:        int,
+	spawner:     Wave_Spawner,
 }
 
 init_world :: proc() -> World {
 	world := World {
 		gold        = 100,
 		base_health = 20,
+		phase       = .Build,
 	}
 	init_map(&world.world_map)
 	build_path(&world.world_map, &world.path)
@@ -27,8 +31,10 @@ update_world :: proc(world: ^World, dt: f32) {
 	cmd := gather_commands(world)
 	execute_command(world, cmd)
 
+	update_wave(world, dt)
 	update_enemies(world, dt)
 	update_towers(world, dt)
+	update_phase(world)
 	process_events(world)
 }