diff --git src/attack.c src/attack.c
index 60bb2ae..4bc7382 100644
--- src/attack.c
+++ src/attack.c
@@ -145,6 +145,9 @@ static bool py_attack_real(int y, int x, bool *fear)
 	bool do_quake = FALSE;
 	bool success = FALSE;
 
+	/* Information about the monster */
+	bool sleep_org = m_ptr->m_timed[MON_TMD_SLEEP];
+
 	/* Default to punching for one damage */
 	const char *hit_verb = "punch";
 	int dmg = 1;
@@ -212,7 +215,7 @@ static bool py_attack_real(int y, int x, bool *fear)
 
 		/* Calculate the damage (including criticals and slays) */
 		dmg = calc_damage(o_ptr, p_ptr->state, slay_index, ATTACK_MELEE,
-			&msg_type, RANDOMISE) / 10;
+			&msg_type, sleep_org ? EXTREMIFY : RANDOMISE) / 10;
 
 		/* Restore state */
 		if (state_hack)