Changeling Titan

Champion reads like a tax and plays like a tether: this enters, and unless you exile another creature you control, it sacrifices itself instead. Pay that cost and you anchor a 7/7 to a creature you already had, with the exiled card waiting to return the instant the Titan leaves the battlefield by any route, death, bounce, or exile all bring it back. That return is the part worth building around, and it cuts two ways. Champion a creature with an enters-the-battlefield trigger and you bank its ETB for later: when the Titan dies, the held creature returns and triggers again on the way in. You are not doubling a trigger so much as putting one in escrow and cashing it on your timeline. The same clause flips Champion from risk to protection: the exiled creature is off the board, untouchable by spot removal and wraths, and the moment something kills the Titan it slides right back into play. Stash a fragile value engine under a disposable body and removal aimed at the Titan becomes free reanimation. The Shapeshifter typing is what makes the package more than a fat green body. Because the Titan reads as a member of every tribe, it counts as on-type for any lord or tribal payoff, and it can Champion any creature regardless of tribe, so it slots into a shell without diluting it. The decision the card is built on is what you bank, and when you want it back.