...sigh. Chuck Norris and Over 9000 were both memes from the past.
Mega Ariados
Typing: Bug/Poison
Ability: Arena Trap
HP: 70
Attack: 90 -> 150
Defense: 70 -> 100
Sp. Attack: 55 -> 30
Sp. Defense: 60 -> 100
Speed: 40 -> 35
Koga's favorite PU Spider turns into a gargantuan moving fortress, laying spider webs all over the place, trapping the opponent.
Mega Ariados is geared toward revenge-killing offensive threats with Sucker Punch and Baton-Passing Agility/Substitute. It's also blessed with an excellent pre-mega ability in Insomnia. Allowing it to switch in against Amoonguss' Spore. Unfortunately, Ariados is easily forced out due to its common weaknesses and its inability to recover its own health without running Rest+Sleep Talk.
Revenge-Killer set:
Baton Pass set:
Hazard Utility set: