It is fitting that I should lead with something gigantic!
And since Onix will be picking up a 6th EC for the match, I'll go ahead and expend 20% of its energy to evolve into Steelix. I've provided stats and attacks updates for Lord Jesseus below.
Abilities will naturally be Rock Head and Sturdy, as they're the only two I've unlocked.
Steelix [Will Powers] (M)
Abilities: Rock Head and Sturdy
Attack: Rank 4 (+)
Defense: Rank 8
SpA: Rank 2
SpD: Rank 3
Spe: 26 (30/1.15v) (-)
We're gonna do it BIIIIIIIG!