actually this can be simplified

src/ship/map/enemy.rs

@@ -99,10 +99,7 @@ impl RareMonsterAppearTable {
     }
 
     pub fn roll_is_rare(&self, monster: &MonsterType) -> bool {
-        if rand_chacha::ChaChaRng::from_entropy().gen::<f32>() < *self.appear_rate.get(monster).unwrap_or(&0.0f32) {
-            return true
-        }
-        false
+        rand_chacha::ChaChaRng::from_entropy().gen::<f32>() < *self.appear_rate.get(monster).unwrap_or(&0.0f32)
     }
 }