It seems like I made a mistake..........there's no Weavile.
In pk3ds it's right below Abomasnow in that species dropdown. Maybe I accidently scrolled it down, ooops sorry. xD
This is the static encounter data for X and Y. (DllField.cro, 0xEE478 - 0xEE506) https://github.com/kwsch/pk3DS/blob/master/pk3DS.Core/Structures/Gen6/EncounterStatic6.cs
CD 02 00 32 FF FF 92 01 27 27 3C 00 // Yveltal
CC 02 00 32 FF FF 92 01 26 26 17 00 // Xerneas
CD 02 00 32 FF FF 92 01 27 27 18 00 // Yveltal
98 02 00 02 FF FF 12 00 00 00 00 00 // Scatterbug
10 00 00 03 FF FF 12 00 00 00 01 00 // Pidgey
90 00 00 46 FF FF 12 01 00 00 1A 00 // Articuno
91 00 00 46 FF FF 12 01 00 00 1A 00 // Zapdos
92 00 00 46 FF FF 12 01 00 00 1A 00 // Moltres
CE 02 00 46 FF FF 12 01 00 00 19 00 // Zygarde
CC 01 00 2D FF FF 92 00 00 00 06 00 // Abomasnow
96 00 00 46 FF FF 12 01 00 00 1A 00 // Mewtwo
CC 02 00 32 FF FF 92 01 26 26 3B 00 // Xerneas
I'm wondering what the last 4 bytes are used for. I thought it might be some sort of assignement so the game knows which map it belongs to, because it's zero for the unused Scatterbug. But where's Abomasnow assigned to then?