1st u need an escape orb, around 99 graverler rocks and a few eyedrop seeds, then you go to floors 94-100 and search 4 a big room(helps if u've got a 1 room orb) ,then use an eyedrop seed and search for a pokemon trap(a circle with a ? in it) when you find it place loads of graverler rock everywhere then step on the trap and mew shoud be one of the pokemon