Mega Sableye's excellent bulk and access to support moves and reliable recovery allow it to be an effective stop to many physical attackers and defensive Pokemon such as Mega Kangaskhan, Garchomp, Chansey, and Cresselia. Its Dark / Ghost typing gives it immunities to Fighting, Normal, and Psychic, a resistance to Poison, and only weak to Fairy. Magic Bounce allows Mega Sableye to effectively bounce back any kind of status move, making it a great status absorber and letting it act as a setup Pokemon that doesn't have to worry about Taunt, Leech Seed, and any status-inducing moves such as Toxic, Will-O-Wisp, and Thunder Wave. Mega Sableye is also the biggest counter to SwagPlay strategies, making your opponent think twice before sending out Klefki, Liepard, and Thundurus. Sableye also has access to Prankster prior to Mega Evolution, which grants its non-damaging moves priority, notably letting it burn its foes with Will-O-Wisp and recover off damage with priority. Sableye uses both the number of physical attackers dominating the metagame and entry hazards being less common in Battle Spot Singles to its advantage by not having to Mega Evolve the first turn, letting it punish Pokemon such as Mega Kangaskhan, Garchomp, and Landorus-T with Prankster Will-O-Wisp and Mega Evolve when it needs to.

Battle Spot Singles is a very fast-paced metagame, which means Sableye can't utilize its stalling capability to its full potential. Even with Mega Sableye's extra bulk, its low HP is a problem. With the Speed decrease after Mega Evolving, Mega Sableye will have huge difficulty outspeeding any threat in the metagame. However, priority STAB Sucker Punch along with its passable Attack after Mega Evolution assists with its terrible Speed. Sableye still lacks offensive presence, though, increasing its reliance on setting up Calm Mind to deal more damage. However, Foul Play helps with that against the monstrous physical attackers of Battle Spot. Also, Sableye is very vulnerable to wallbreakers and setup sweepers such as Hydreigon, Mega Charizard X, Serperior, and Thundurus, so leaving it in against those threats would mean trouble for the jewel thief.