Add case for special headbutt slots

Closes #3174

Add more xmldoc for SlotType

Import revised slot-type table, as we've removed "Special" from the regular trees.
ef4b1b2894

PKHeX.Core/Legality/Enums/SlotType.cs

@@ -61,15 +61,41 @@ namespace PKHeX.Core
         /// </summary>
         BugContest = 9,
 
+        /// <summary>
+        /// Slot is encountered via Generation 5 Hidden Grotto.
+        /// </summary>
         HiddenGrotto = 10,
-        // GoPark = 11,
-        FriendSafari = 12,
-        Horde = 13,
-        // Pokeradar = 14,
-        SOS = 15,
-        // always used as a modifier to another slot type
 
+        // GoPark = 11, UNUSED, now EncounterSlot7g
+
+        /// <summary>
+        /// Slot is encountered via Generation 6 Friend Safari.
+        /// </summary>
+        FriendSafari = 12,
+
+        /// <summary>
+        /// Slot is encountered via Generation 6 Horde Battle.
+        /// </summary>
+        Horde = 13,
+
+        // Pokeradar = 14, // UNUSED, don't need to differentiate Gen4 Radar Slots
+
+        /// <summary>
+        /// Slot is encountered via Generation 7 SOS triggers only.
+        /// </summary>
+        SOS = 15,
+
+        // Modifiers
+
+        /// <summary>
+        /// Used to differentiate the two types of headbutt tree encounters.
+        /// </summary>
+        /// <remarks><see cref="Headbutt"/></remarks>
         Special = 1 << 6,
+
+        /// <summary>
+        /// Used to identify encounters that are triggered via alternate ESV proc calculations.
+        /// </summary>
         Swarm = 1 << 7,
     }
 

PKHeX.Core/Legality/RNG/Frame/SlotRange.cs

@@ -48,7 +48,7 @@ namespace PKHeX.Core
                 SlotType.Rock_Smash or SlotType.Surf => CalcSlot(ESV, H_Surf),
                 SlotType.Super_Rod or SlotType.Good_Rod or SlotType.Old_Rod => CalcSlot(ESV, K_SuperRod),
                 SlotType.BugContest => CalcSlot(ESV, K_BCC),
-                SlotType.Headbutt => CalcSlot(ESV, K_Headbutt),
+                SlotType.Headbutt or SlotType.Headbutt | SlotType.Special => CalcSlot(ESV, K_Headbutt),
                 _ => CalcSlot(ESV, H_Regular)
             };
         }