Implement monster swiftness, and give it to Gastronok

8 files changed, 33 insertions, 6 deletions

diff --git a/crawl-ref/source/directn.cc b/crawl-ref/source/directn.cc
index 78c9f5ce24..3d225bfd6c 100644
--- a/crawl-ref/source/directn.cc
+++ b/crawl-ref/source/directn.cc
@@ -2968,6 +2968,7 @@ static std::string _describe_mons_enchantment(const monsters &mons,
     // Suppress silly-looking combinations, even if they're
     // internally valid.
     if (paralysed && (ench.ench == ENCH_SLOW || ench.ench == ENCH_HASTE
+                      || ench.ench == ENCH_SWIFT
                       || ench.ench == ENCH_PETRIFIED
                       || ench.ench == ENCH_PETRIFYING))
     {
@@ -3009,6 +3010,7 @@ static std::string _describe_mons_enchantment(const monsters &mons,
     case ENCH_PETRIFIED:     return "petrified";
     case ENCH_PETRIFYING:    return "slowly petrifying";
     case ENCH_LOWERED_MR:    return "susceptible to magic";
+    case ENCH_SWIFT:         return "moving somewhat quickly";
     default:                 return "";
     }
 }
diff --git a/crawl-ref/source/enum.h b/crawl-ref/source/enum.h
index 4f0684d1d4..e5f8b56b5d 100644
--- a/crawl-ref/source/enum.h
+++ b/crawl-ref/source/enum.h
@@ -1246,6 +1246,7 @@ enum enchant_type
     ENCH_AQUATIC_LAND,   // Water monsters lose hp while on land.
     ENCH_SPORE_PRODUCTION,             //   35
     ENCH_SLOUCH,
+    ENCH_SWIFT,
 
     // Update enchantment names in mon-util.cc when adding or removing
     // enchantments.
diff --git a/crawl-ref/source/ghost.cc b/crawl-ref/source/ghost.cc
index 0bfb9a0938..6cb75f44d0 100644
--- a/crawl-ref/source/ghost.cc
+++ b/crawl-ref/source/ghost.cc
@@ -85,6 +85,7 @@ static spell_type search_order_third[] = {
     SPELL_DEMONIC_HORDE,
     SPELL_HASTE,
     SPELL_SUMMON_UGLY_THING,
+    SPELL_SWIFTNESS,
     SPELL_SUMMON_ICE_BEAST,
     SPELL_ANIMATE_DEAD,
 // 10
diff --git a/crawl-ref/source/item_use.cc b/crawl-ref/source/item_use.cc
index 94672df38d..e9a0160bea 100644
--- a/crawl-ref/source/item_use.cc
+++ b/crawl-ref/source/item_use.cc
@@ -5065,6 +5065,7 @@ static void _vulnerability_scroll()
     const enchant_type lost_enchantments[] = {
         ENCH_SLOW,
         ENCH_HASTE,
+        ENCH_SWIFT,
         ENCH_MIGHT,
         ENCH_FEAR,
         ENCH_CONFUSION,
diff --git a/crawl-ref/source/mon-cast.cc b/crawl-ref/source/mon-cast.cc
index a07ad8987c..abf7869571 100644
--- a/crawl-ref/source/mon-cast.cc
+++ b/crawl-ref/source/mon-cast.cc
@@ -784,6 +784,7 @@ bool setup_mons_cast(monsters *monster, bolt &pbolt, spell_type spell_cast,
     case SPELL_SUMMON_GREATER_DEMON:
     case SPELL_CANTRIP:
     case SPELL_BERSERKER_RAGE:
+    case SPELL_SWIFTNESS:
     case SPELL_WATER_ELEMENTALS:
     case SPELL_FIRE_ELEMENTALS:
     case SPELL_AIR_ELEMENTALS:
@@ -1600,6 +1601,11 @@ void mons_cast(monsters *monster, bolt &pbolt, spell_type spell_cast,
         monster->go_berserk(true);
         return;
 
+    case SPELL_SWIFTNESS:
+        monster->add_ench(ENCH_SWIFT);
+        simple_monster_message(monster, " seems to move somewhat quicker.");
+        return;
+
     case SPELL_SUMMON_SMALL_MAMMALS:
     case SPELL_VAMPIRE_SUMMON:
         if (spell_cast == SPELL_SUMMON_SMALL_MAMMALS)
diff --git a/crawl-ref/source/mon-spll.h b/crawl-ref/source/mon-spll.h
index e246092c2a..118410f0ab 100644
--- a/crawl-ref/source/mon-spll.h
+++ b/crawl-ref/source/mon-spll.h
@@ -1100,7 +1100,7 @@
       {
        SPELL_AIRSTRIKE,
        SPELL_SLOW,
-       SPELL_AIRSTRIKE,
+       SPELL_SWIFTNESS,
        SPELL_SUMMON_SMALL_MAMMALS,
        SPELL_CANTRIP,
        SPELL_AIRSTRIKE,
diff --git a/crawl-ref/source/mon-util.cc b/crawl-ref/source/mon-util.cc
index 06ec8b7a61..d070c47b98 100644
--- a/crawl-ref/source/mon-util.cc
+++ b/crawl-ref/source/mon-util.cc
@@ -2209,6 +2209,7 @@ bool ms_useful_fleeing_out_of_sight( const monsters *mon, spell_type monspell )
     switch (monspell)
     {
     case SPELL_HASTE:
+    case SPELL_SWIFTNESS:
     case SPELL_INVISIBILITY:
     case SPELL_MINOR_HEALING:
     case SPELL_MAJOR_HEALING:
@@ -2369,6 +2370,11 @@ bool ms_waste_of_time( const monsters *mon, spell_type monspell )
             ret = true;
         break;
 
+    case SPELL_SWIFTNESS:
+        if (mon->has_ench(ENCH_SWIFT))
+            ret = true;
+        break;
+
     case SPELL_INVISIBILITY:
         if (mon->has_ench(ENCH_INVIS)
             || mon->friendly() && !you.can_see_invisible(false))
@@ -2522,6 +2528,7 @@ static bool _ms_ranged_spell(spell_type monspell, bool attack_only = false,
     case SPELL_INVISIBILITY:
     case SPELL_BLINK:
     case SPELL_BERSERKER_RAGE:
+    case SPELL_SWIFTNESS:
         return (false);
 
     // The animation spells don't work through transparent walls and thus
diff --git a/crawl-ref/source/monster.cc b/crawl-ref/source/monster.cc
index 29d192cfd3..0c963631c7 100644
--- a/crawl-ref/source/monster.cc
+++ b/crawl-ref/source/monster.cc
@@ -4207,6 +4207,11 @@ void monsters::remove_enchantment_effect(const mon_enchant &me, bool quiet)
             simple_monster_message(this, " is no longer moving quickly.");
         break;
 
+    case ENCH_SWIFT:
+        if (!quiet)
+            simple_monster_message(this, " is no longer moving somewhat quickly.");
+        break;
+
     case ENCH_MIGHT:
         if (!quiet)
             simple_monster_message(this, " no longer looks unusually strong.");
@@ -4519,7 +4524,7 @@ void monsters::timeout_enchantments(int levels)
         case ENCH_SLOW: case ENCH_HASTE: case ENCH_MIGHT: case ENCH_FEAR:
         case ENCH_INVIS: case ENCH_CHARM:  case ENCH_SLEEP_WARY:
         case ENCH_SICK:  case ENCH_SLEEPY: case ENCH_PARALYSIS:
-        case ENCH_PETRIFYING: case ENCH_PETRIFIED:
+        case ENCH_PETRIFYING: case ENCH_PETRIFIED: case ENCH_SWIFT:
         case ENCH_BATTLE_FRENZY: case ENCH_NEUTRAL:
         case ENCH_LOWERED_MR: case ENCH_SOUL_RIPE:
             lose_ench_levels(i->second, levels);
@@ -4653,6 +4658,7 @@ void monsters::apply_enchantment(const mon_enchant &me)
 
     case ENCH_SLOW:
     case ENCH_HASTE:
+    case ENCH_SWIFT:
     case ENCH_MIGHT:
     case ENCH_FEAR:
     case ENCH_PARALYSIS:
@@ -5616,12 +5622,14 @@ const monsterentry *monsters::find_monsterentry() const
 
 int monsters::action_energy(energy_use_type et) const
 {
+    bool swift = has_ench(ENCH_SWIFT);
+
     if (const monsterentry *me = find_monsterentry())
     {
         const mon_energy_usage &mu = me->energy_usage;
         switch (et)
         {
-        case EUT_MOVE:    return mu.move;
+        case EUT_MOVE:    return mu.move - (swift ? 2 : 0);
         case EUT_SWIM:
             // [ds] Amphibious monsters get a significant speed boost
             // when swimming, as discussed with dpeg. We do not
@@ -5630,9 +5638,9 @@ int monsters::action_energy(energy_use_type et) const
             // favour water (HT_AMPHIBIOUS_WATER, such as merfolk), but
             // that's something we can think about.
             if (mons_amphibious(this))
-                return div_rand_round(mu.swim * 7, 10);
+                return div_rand_round(mu.swim * 7, 10) - (swift ? 2 : 0);
             else
-                return mu.swim;
+                return mu.swim - (swift ? 2 : 0);
         case EUT_MISSILE: return mu.missile;
         case EUT_ITEM:    return mu.item;
         case EUT_SPECIAL: return mu.special;
@@ -5885,7 +5893,7 @@ static const char *enchant_names[] =
     "short-lived", "paralysis", "sick", "sleep", "fatigue", "held",
     "blood-lust", "neutral", "petrifying", "petrified", "magic-vulnerable",
     "soul-ripe", "decay", "hungry", "flopping", "spore-producing",
-    "downtrodden", "bug"
+    "downtrodden", "swift", "bug"
 };
 
 static const char *_mons_enchantment_name(enchant_type ench)
@@ -5986,6 +5994,7 @@ int mon_enchant::calc_duration(const monsters *mons,
     switch (ench)
     {
     case ENCH_HASTE:
+    case ENCH_SWIFT:
     case ENCH_MIGHT:
     case ENCH_INVIS:
         cturn = 1000 / _mod_speed(25, mons->speed);