Here's my try at a Vicious Rejuvenation deck.
The idea being to hurt yourself, surprise em with the old health total switcheroo, and finish them off.
I usually shift my Cen Wastes Smugglers, the unblockable can come in handy after the switch.
On redraws try to get a hand with a merchant and power. Fenris nightshade is great early too, it's often correct to spend 3 just activating it.
It's pretty common that you can't win on the turn you switch, following up with blast/torch is often necessary. Brawler stops them from gaining health after you switch.
This deck induces a lot of salty emote spamming, so mute first if you don't like that. Or enjoy it if you do.