Mega Meganium
Grass/Fairy
Petal Shield - Won't take dmg less than or equal to 25%
HP 80
Atk 122 (+40)
Def 130 (+30)
Sp. Atk 83
Sp. Def 130 (+30)
Speed 80
Typical set: Play Rough, Earthquake, Wild Charge, Substitute
Mega Typhlosion
Fire/Electric
No Guard
HP 78
Attack 84
Defense 118 (+40)
Sp. Atk 124 (+15)
Sp. Def 95 (+20)
Speed 125 (+25)
Typical set: Inferno, Zap Cannon, Focus Blast, Hidden Power Ice
Mega Feraligatr
Water/Dark
Water Veil
HP 85
Attack 145 (+40)
Defense 125 (+25)
Sp. Atk 79
Sp. Def 83
Speed 113 (+35)
Typical set: Dragon Dance, Aqua Tail, Crunch, etc
Mega Flygon
Ground/Dragon
Pestilate (Bug type "-ate", provides third semi-STAB)
HP 80
Atk 70 (-30, same as Vibrava)
Def 110 (+30, same as Vibrava -> Flygon)
Sp. Atk 125 (+45, opposite Atk/Sp. Atk diff as Trapinch)
Sp. Def 110 (+30, same as Vibrava -> Flygon)
Speed 135 (+35, dump stat)
Typical Set: Quiver Dance, Boomburst, Earth Power, Dragon Pulse
M-Masquerain
Bug/Water, Serene Grace
HP 70
Atk 60
Def 97 (62+35)
SpA 100 (80+20)
SpD 97 (82+15)
Spe 90 (60+30)
Good set: Quiver Dance/Scald/Bug Buzz/Freeze-Dry (added)
M-Vivillon
Bug/Fairy, Protean
HP 80
Atk 52
Def 80 (50+30)
SpA 110 (90+20)
SpD 80 (50+30)
Spe 109 (89+20)
Good set: Quiver Dance/Aura Sphere (added)/Psychic/Hidden Power [Ghost]
Eevee, new moves: Extremespeed/Crunch/Close Combat/Aura Sphere/Acrobatics/Play Rough/Work Up
Mega Vaporeon: (Serene Grace) 130 HP/65 Atk/85 Def/135 SpA/120 SpD/90 Spe
Mega Jolteon: (Sheer Force) 65 HP/65 Atk/85 Def/135 SpA/120 SpD/155 Spe
Mega Flareon: (Huge Power) 65 HP/155 Atk/120 Def/60 SpA/135 SpD/90 Spe
Mega Espeon: (Cloud Nine) 65 HP/65 Atk/85 Def/155 SpA/120 SpD/135 Spe
Mega Umbreon: (Magic Guard) 95 HP/60 Atk/135 Def/90 SpA/155 SpD/90 Spe
Mega Leafeon: (Filter) 65 HP/135 Atk/155 Def/60 SpA/90 SpD/120 Spe (Level Up: Aqua Tail)
Mega Glaceon: (Weak Armor) 65 HP/60 Atk/135 Def/155 SpA/120 SpD/90 Spe (Level Up: Freeze-Dry)
Mega Sylveon: (Regenerator) 95 HP/65 Atk/90 Def/135 SpA/155 SpD/85 Spe