It brings a mercenary token along for the ride, and that token can buff attackers to swing combat in your favor
There's also some often overlooked SIRs such as Roaring Moon ex, Ceruledge ex, and Dragapult ex to boot
Ground shakes up Electric , Rock , Poison , Fire , and Steel
So with this Greninja card, I would recommend setting it up on the bench, then if your opponent is using an Ability, move this card into the active Pokemon spot and use Shadow Stitching every turn, thus disabling your opponent's Ability
Sometimes your deck makes Slugs and your token binder says good luck. Better: Reskin a real token with custom art This is the sweet spot for most people: keep the tokens rules text and stats the same, but give it horror art that matches your commander, your theme, or your personal brand of nightmare fuel