Index: src/attack.c
===================================================================
--- src/attack.c	(revision 694)
+++ src/attack.c	(working copy)
@@ -189,7 +189,25 @@
 }
 
 
+/*
+ * Adjust the input damage based on how many times the character has
+ * killed a given monster.
+ *
+ *
+ */
 
+static int learned_slay_adj(int base_damage, const monster_type *m_ptr)
+{
+	monster_lore *l_ptr = &l_list[m_ptr->r_idx];
+	
+	if(l_ptr->pkills >= 0 && l_ptr->pkills <= 1000){
+		return base_damage  + (( base_damage * 10 * l_ptr->pkills) / 1000 ) / 10;
+	} else {
+		return base_damage  + (( 2 * base_damage * 10 * l_ptr->pkills) / 10000 ) / 10;
+	}
+
+}
+
 /*
  * Extract the "multiplier" from a given object hitting a given monster.
  *
@@ -393,7 +411,6 @@
 		}
 	}
 
-
 	/* Return the multiplier */
 	return (mult);
 }
@@ -407,7 +424,7 @@
  */
 void py_attack(int y, int x)
 {
-	int num = 0, k, bonus, chance;
+	int num = 0, k, old_k, bonus, chance;
 
 	monster_type *m_ptr;
 	monster_race *r_ptr;
@@ -491,13 +508,20 @@
 			/* Apply the player damage bonuses */
 			k += p_ptr->to_d;
 
+			/* apply the player learned slay bonus */
+			if (p_ptr->wizard)
+			{
+				old_k = k;
+			}
+			k = learned_slay_adj(k, m_ptr);
+
 			/* No negative damage */
 			if (k < 0) k = 0;
 
 			/* Complex message */
 			if (p_ptr->wizard)
 			{
-				msg_format("You do %d (out of %d) damage.", k, m_ptr->hp);
+				msg_format("You do %d[%d] (out of %d) damage.", k, old_k, m_ptr->hp);
 			}
 
 			/* Damage, check for fear and death */