A 2HKO strategy against Pokemon-GX, Pokemon VMAX, and Tag Team Pokemon-GX can work well for non-GX/V decks (Arceus and Dialga and Palkia-GX notwithstanding), but the difficulty of establishing a Stage-2 attacker generally results in the 2HKO strategy falling short for Stage-2 decks
Coretapper also speeds up charge counter production, with a sacrifice ability that lets you put two charge counters on a target artifact
Thats right, its effect is always active if you just put your cards on the table and play with no cards in your hand
Here's how the deck looks with the upgrades added: Further Upgrades There's a bunch of heavy-hitter Phyrexians you can toss in the top-end: Elesh Norn, Mother of Machines and Mondrak, Glory Dominus both double the amount of tokens you're incubating with Brimaz which is super sweet, Elesh Norn is a great anthem for incubation, plus there's Sheoldred, Sheoldred, Whispering One, Sheoldred, the Apocalypse (lots of Sheoldreds!),Wurmcoil Engine, Skithiryx, the Blight Dragon