diff --git a/src/ship/packet/handler/message.rs b/src/ship/packet/handler/message.rs
index c1efe6b..937a08c 100644
--- a/src/ship/packet/handler/message.rs
+++ b/src/ship/packet/handler/message.rs
@@ -26,7 +26,7 @@ pub async fn request_exp<EG: EntityGateway>(id: ClientId,
         .ok_or_else(|| ShipError::InvalidRoom(room_id.0 as u32))?;
 
     let monster = room.maps.enemy_by_id(request_exp.enemy_id as usize)?;
-    let monster_stats = room.monster_stats.get(&monster.monster).unwrap();
+    let monster_stats = room.monster_stats.get(&monster.monster).ok_or(ShipError::UnknownMonster(monster.monster.clone()))?;
 
     let exp_gain = if request_exp.last_hitter == 1 {
         monster_stats.exp
diff --git a/src/ship/ship.rs b/src/ship/ship.rs
index d431c96..ddbcb2d 100644
--- a/src/ship/ship.rs
+++ b/src/ship/ship.rs
@@ -66,6 +66,7 @@ pub enum ShipError {
     NotEnoughMeseta(ClientId, u32),
     ShopError,
     GatewayError(#[from] GatewayError),
+    UnknownMonster(crate::ship::monster::MonsterType),
 }
 
 #[derive(Debug)]