This list is missing some of the Megas such as Golisopod, Baxcalibur, Tatsugiri, the Z Megas, and the legendary & mythical Megas, because they aren't in Champions yet.
Mega Raichu X - Electric Surge
Mega Raichu Y - No Guard
Mega Clefable - Magic Bounce
Mega Victreebel - Innards Out
Mega Starmie - Huge Power
Mega Dragonite - Multiscale
Mega Meganium - Mega Sol (uses all moves as if sunlight was active)
Mega Feraligatr - Dragonize (Refrigerate/Pixelate but for Dragon)
Mega Skarmory - Stalwart
Mega Chimecho - Levitate (Bronzong who?)
Mega Staraptor - Contrary
Mega Froslass - Snow Warning
Mega Emboar - Mold Breaker
Mega Excadrill - Piercing Drill (Aka nerfed Unseen Fist)
Mega Scolipede - Shell Armor
Mega Scrafty - Intimidate
Mega Elektross - Elevate (Levitate + Beast Boost)
Mega Chandelure - Infiltrator
Mega Golurk - Unseen Fist (but it's nerfed now)
Mega Chesnaught - Bulletproof
Mega Delphox - Levitate
Mega Greninja - Protean
Mega Pyroar - Fire Mane (boosts Fire type moves by 50%)
Mega Floette - Fairy Aura
Mega Meowstic - Trace
Mega Malamar - Contrary
Mega Barbaracle - Tough Claws
Mega Dragalge - Regenerator
Mega Hawlucha - No Guard
Mega Crabominable - Iron Fist
Mega Drampa - Berserk
Mega Falinks - Defiant
Mega Scovillian - Spicy Spray (if damaged, its attacker is burnt)
Mega Glimmora - Adaptability
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