Mega Sableye is a great Pokemon due to a great pre-Mega Evolution ability in Prankster and a great post-Mega Evolution ability in Magic Bounce. Prankster Will-O-Wisp allows it to burn physical attackers easily, and Magic Bounce allows Mega Sableye to counter Klefki, a major threat in the metagame, as well as pivot into other entry hazard setters and status users such as Arceus-Fairy, making Mega Sableye extremely good on stall archetypes. Its dual typing grants it three immunities, including an immunity to Arceus's and Mega Rayquaza's Extreme Speed, and only one weakness. It is also one of the best defensive Deoxys-A and Mewtwo checks there is, Pokemon that otherwise decimate stall. Unfortunately, Sableye is very slow and loses Prankster after it Mega Evolves, making it easy to take advantage of. Due to the prevalence of Klefki and Darkrai in Anything Goes, there are a ton of status absorbers, which hurts Mega Sableye a lot. Mega Sableye is also often overwhelmed by the sheer power of the attackers of the metagame, and even the Pokemon it is supposed to check can often annoy it with some sets, such as Magic Coat Arceus and special Mega Rayquaza. Even defensive Pokemon such as Arceus-Water and Lava Plume Primal Groudon can KO Mega Sableye, and Fairy-type Pokemon put a ton of pressure on it. Mega Sableye is also a complete momentum suck and only really fits on full stall and occasionally on balance teams.