Platinum's gatehouse is my favourite of the 4th gen, so I was surprised to find no one had made tiles. Finally after an hour I got it perfect, and because it took me so long, I've decided to put it on here for everyone to use!
Update: Added the South/North Gatehouse tiles.
Update 2: I've added the outsides of the gatehouses, so now it's 100% complete. The original tile can be found here: [link]
but I've heavily edited it and created the west/east one, so give credit to me as well as Reck if you use them.
Credit to Alucus for the bush, Reck for original exterior base and to me for the rest.