Retaliation from monster minotaurs.

This makes an already very dangerous monster even more deadly though,
encouraging kiting.  We may want to investigate this.  This commit provides
consistency with players, though.

crawl-ref/source/hiscores.cc

@@ -427,7 +427,7 @@ static const char *kill_method_names[] =
     "tso_smiting", "petrification", "something",
     "falling_down_stairs", "acid", "curare",
     "beogh_smiting", "divine_wrath", "bounce", "reflect", "self_aimed",
-    "falling_through_gate", "disintegration",
+    "falling_through_gate", "disintegration", "headbutt",
 };
 
 const char *kill_method_name(kill_method_type kmt)
@@ -925,6 +925,7 @@ void scorefile_entry::init_death_cause(int dam, int dsrc,
     }
     // for death by monster
     if ((death_type == KILLED_BY_MONSTER
+            || death_type == KILLED_BY_HEADBUTT
             || death_type == KILLED_BY_BEAM
             || death_type == KILLED_BY_DISINT
             || death_type == KILLED_BY_SPORE
@@ -1649,6 +1650,14 @@ std::string scorefile_entry::death_description(death_desc_verbosity verbosity)
             needs_damage = true;
         break;
 
+    case KILLED_BY_HEADBUTT:
+        if (terse)
+            desc += apostrophise(death_source_desc()) + " headbutt";
+        else
+            desc += "Headbutted by " + death_source_desc();
+        needs_damage = true;
+        break;
+
     case KILLED_BY_POISON:
         if (death_source_name.empty() || terse)
         {

crawl-ref/source/melee_attack.cc

@@ -387,9 +387,7 @@ bool melee_attack::handle_phase_dodged()
             // TODO: Unify these, placed player_warn_miss here so I can remove
             // player_attack
             if (attacker->atype() == ACT_PLAYER)
-            {
                 player_warn_miss();
-            }
             else
             {
                 mprf("%s%s misses %s%s",
@@ -402,15 +400,17 @@ bool melee_attack::handle_phase_dodged()
     }
 
     if (attacker != defender &&
-        defender->atype() == ACT_PLAYER &&
-        grid_distance(you.pos(), attacker->as_monster()->pos()) == 1)
+        grid_distance(defender->pos(), attacker->pos()) == 1)
     {
         // Only half the normal chance of retaliation for attacks after the
         // first one.
-        if (attacker->alive() &&
-            you.species == SP_MINOTAUR &&
-            you.can_see(attacker) &&
-            (effective_attack_number == 0 || coinflip()))
+        if (attacker->alive()
+            && (defender->is_player() ?
+                   you.species == SP_MINOTAUR :
+                   mons_base_type(defender->as_monster()) == MONS_MINOTAUR)
+            && defender->can_see(attacker)
+            // FIXME: player's attack is -1, even for auxes
+            && effective_attack_number <= 0)
         {
             do_minotaur_retaliation();
         }
@@ -4428,23 +4428,54 @@ void melee_attack::emit_foul_stench()
 
 void melee_attack::do_minotaur_retaliation()
 {
+    if (defender->cannot_act() || !attacker->alive())
+        return;
+
+    if (!defender->is_player())
+    {
+        // monsters have no STR or DEX
+        if (!x_chance_in_y(5, 5))
+            return;
+
+        int hurt = random2(20) - attacker->armour_class();
+        if (you.see_cell(defender->pos()))
+        {
+            const std::string defname = defender->name(DESC_THE);
+            mprf("%s furiously retaliates!", defname.c_str());
+            if (hurt <= 0)
+            {
+                mprf("%s headbutts %s, but does no damage.", defname.c_str(),
+                     attacker->name(DESC_THE).c_str());
+            }
+            else
+            {
+                mprf("%s headbutts %s%s", defname.c_str(),
+                     attacker->name(DESC_THE).c_str(),
+                     get_exclams(hurt).c_str());
+            }
+        }
+        if (hurt > 0)
+        {
+            if (attacker->is_player())
+                ouch(hurt, defender->mindex(), KILLED_BY_HEADBUTT);
+            else
+                attacker->hurt(defender, hurt);
+        }
+        return;
+    }
+
     if (!(you.form == TRAN_NONE || you.form == TRAN_APPENDAGE
           || you.form == TRAN_BLADE_HANDS || you.form == TRAN_STATUE
           || you.form == TRAN_LICH))
     {
         // You are in a non-minotaur form.
         return;
     }
-    if (you.cannot_act())
-    {
-        // You can't move.
-        return;
-    }
     // This will usually be 2, but could be 3 if the player mutated more.
     const int mut = player_mutation_level(MUT_HORNS);
     const int slaying = slaying_bonus(PWPN_DAMAGE);
 
-    if (attacker->alive() && 5*you.strength() + 7*you.dex() > random2(600))
+    if (5 * you.strength() + 7 * you.dex() > random2(600))
     {
         // Use the same damage formula as a regular headbutt.
         int dmg = 5 + mut * 3;
@@ -4473,7 +4504,6 @@ void melee_attack::do_minotaur_retaliation()
             attacker->hurt(&you, hurt);
         }
     }
-    return;
 }
 
 bool melee_attack::do_knockback(bool trample)

crawl-ref/source/ouch.h

@@ -53,6 +53,7 @@ enum kill_method_type
     KILLED_BY_SELF_AIMED,
     KILLED_BY_FALLING_THROUGH_GATE,
     KILLED_BY_DISINT,
+    KILLED_BY_HEADBUTT,
 
     NUM_KILLBY
 };