diff --git a/inc/conf.h b/inc/conf.h
index f4eebe6..a635acc 100644
--- a/inc/conf.h
+++ b/inc/conf.h
@@ -5,10 +5,13 @@
 #define PLAYER_WIDTH        14
 #define PLAYER_HEIGHT       14
 #define GRAVITY             0.2f
-#define AIR_RESISTANCE      0.02f
+#define AIR_RESISTANCE      0.03f
 #define MAX_WALK_SPEED      2.0f
 #define ACCELERATION_AIR    0.1f
 #define ACCELERATION_GROUND 0.4f
 #define FRICTION_AIR        (ACCELERATION_AIR / MAX_WALK_SPEED)
 #define FRICTION_GROUND     (ACCELERATION_GROUND / MAX_WALK_SPEED)
 #define FRICTION_BREAK      (0.6f / MAX_WALK_SPEED)
+#define JUMP_GRACE          4
+#define JUMP_BUFFER         12
+#define JUMP_SPD            -5.0
diff --git a/inc/input.h b/inc/input.h
index d73de49..39eb248 100644
--- a/inc/input.h
+++ b/inc/input.h
@@ -1,7 +1,7 @@
 #pragma once
 /* use this to get user input, NOT gint/keyboard.h */
 
-enum Key { K_A, K_B, K_UP, K_DOWN, K_LEFT, K_RIGHT, K_EXIT, K_COUNT };
+enum Key { K_JUMP, K_PUNCH, K_UP, K_DOWN, K_LEFT, K_RIGHT, K_EXIT, K_COUNT };
 enum KeyState { KS_UP, KS_RELEASE, KS_DOWN, KS_PRESS };
 
 struct Input {
diff --git a/inc/particles.h b/inc/particles.h
index 51fbd0f..96f8d46 100644
--- a/inc/particles.h
+++ b/inc/particles.h
@@ -7,3 +7,4 @@ void particles_init(void);
 void particles_add(struct Anim);
 void particles_update(void);
 void particles_draw(void);
+int particles_here(int x, int y);
diff --git a/inc/player.h b/inc/player.h
index bcd9025..5b47114 100644
--- a/inc/player.h
+++ b/inc/player.h
@@ -5,6 +5,8 @@ struct Player {
 	struct Vec pos;
 	struct VecF spd;
 	struct VecF rem;
+	int jump_grace;
+	int jump_buffer;
 };
 
 void player_init(struct Vec pos);
diff --git a/inc/tile.h b/inc/tile.h
index 4519eb9..2a238ed 100644
--- a/inc/tile.h
+++ b/inc/tile.h
@@ -1,3 +1,9 @@
 #pragma once
 
-enum Tile { TILE_VOID, TILE_SOLID, TILE_PLAYER, TILE_OOB = TILE_SOLID };
+enum Tile {
+	TILE_VOID,
+	TILE_SOLID,
+	TILE_PLAYER,
+	TILE_SHATTERED,
+	TILE_OOB = TILE_SOLID
+};
diff --git a/res/tileset.png b/res/tileset.png
index 47b7789..6e2ea9e 100644
Binary files a/res/tileset.png and b/res/tileset.png differ
diff --git a/src/input.c b/src/input.c
index 4f3cbda..bd87fc4 100644
--- a/src/input.c
+++ b/src/input.c
@@ -10,8 +10,8 @@ input_init(void)
 	while (i-- > 0) {
 		input.states[i] = KS_UP;
 	}
-	input.keys[K_A] = KEY_SHIFT;
-	input.keys[K_B] = KEY_ALPHA;
+	input.keys[K_JUMP] = KEY_SHIFT;
+	input.keys[K_PUNCH] = KEY_ALPHA;
 	input.keys[K_LEFT] = KEY_LEFT;
 	input.keys[K_RIGHT] = KEY_RIGHT;
 	input.keys[K_UP] = KEY_UP;
diff --git a/src/main.c b/src/main.c
index 9a5beab..401a37a 100644
--- a/src/main.c
+++ b/src/main.c
@@ -31,7 +31,7 @@ main(void)
 	player_init(level_find(TILE_PLAYER));
 	camera_init(player_pos());
 
-	while (!input_pressed(K_EXIT)) {
+	while (!input_down(K_EXIT)) {
 		int i;
 		draw();
 		for (i = 0; i < frameskip; i++) {
diff --git a/src/particles.c b/src/particles.c
index 3cce7ac..7a0212d 100644
--- a/src/particles.c
+++ b/src/particles.c
@@ -37,3 +37,14 @@ particles_draw(void)
 	while (i-- > 0)
 		anim_draw(&particles[i]);
 }
+
+int
+particles_here(int x, int y)
+{
+	int i = MAX_PARTICLES;
+	while (i-- > 0) {
+		if (particles[i].pos.x == x && particles[i].pos.y == y)
+			return 1;
+	}
+	return 0;
+}
diff --git a/src/player.c b/src/player.c
index 752dd4d..b5166a8 100644
--- a/src/player.c
+++ b/src/player.c
@@ -10,6 +10,7 @@
 
 static struct Player self;
 
+static void jump(int on_ground);
 static int collide_solid(int x, int y);
 
 void
@@ -18,6 +19,8 @@ player_init(struct Vec pos)
 	self.pos = pos;
 	self.spd = VECFZ;
 	self.rem = VECFZ;
+	self.jump_grace = 0;
+	self.jump_buffer = 0;
 }
 
 void
@@ -42,12 +45,37 @@ player_update(void)
 	self.spd.y *= 1.0f - AIR_RESISTANCE;
 	self.spd.y += GRAVITY;
 
-	if (input_pressed(K_DOWN))
-		shatter(self.pos.x, self.pos.y + PLAYER_HEIGHT);
+	jump(on_ground);
 
 	player_move(player_update_rem());
 }
 
+static void
+jump(int on_ground)
+{
+	/* grace */
+	if (on_ground)
+		self.jump_grace = JUMP_GRACE;
+	else if (self.jump_grace)
+		self.jump_grace--;
+	/* buffer */
+	if (input_pressed(K_JUMP))
+		self.jump_buffer = JUMP_BUFFER;
+	else if (self.jump_buffer)
+		self.jump_buffer--;
+	/* jump */
+	if (self.jump_grace && self.jump_buffer && input_down(K_JUMP)) {
+		struct Vec shatter_pos = VEC(self.pos.x, self.pos.y);
+		self.jump_grace = 0;
+		self.jump_buffer = 0;
+		self.spd.y = JUMP_SPD;
+		shatter_pos.y += PLAYER_HEIGHT;
+		shatter(shatter_pos.x, shatter_pos.y);
+		shatter_pos.x += PLAYER_WIDTH - 1;
+		shatter(shatter_pos.x, shatter_pos.y);
+	}
+}
+
 void
 player_draw(void)
 {
diff --git a/src/shatter.c b/src/shatter.c
index 4fd0edd..bdf6578 100644
--- a/src/shatter.c
+++ b/src/shatter.c
@@ -17,11 +17,12 @@ shatter(int x, int y)
 	const int ay = (int)(y / TILE_SIZE) * TILE_SIZE;
 	struct Anim p = anim_new(&bimg_shatter, ax, ay, TILE_SIZE, 2, false);
 	p.callback = callback;
-	particles_add(p);
+	if (level_get_px(ax, ay) == TILE_SOLID && !particles_here(ax, ay))
+		particles_add(p);
 }
 
 static void
 callback(struct Anim *a)
 {
-	level_set_px(a->pos.x, a->pos.y, TILE_PLAYER);
+	level_set_px(a->pos.x, a->pos.y, TILE_SHATTERED);
 }