Fblthp, the Lost

The joke is that the mascot who has spent his entire existence getting lost is now mechanically rewarded for wandering out of your library, and the design commits hard enough to make the bit functional. The base line replaces itself the moment he lands, but the payoff doubles when he enters or is cast from the library rather than the hand: two cards instead of one. That condition is narrow on purpose. Milling him doesn't count, because milling drops cards into the graveyard; the doubled draw wants effects that put him onto the battlefield directly from the deck or let you cast him off the top, which reframes library-manipulation and cheat-into-play effects as ways to squeeze the extra card. The second ability is self-protection written straight out of the flavor: aim a spell at Fblthp and he panics back into your library, dodging targeted removal while conveniently reloading the "cast from library" condition. Read together, the two triggers point toward a loop where the creature wants to keep being shuffled away and found again, each round netting cards. It is a rare case of a comedic mascot whose design maps his personality onto function: the effect isn't decoration on a value body, it is the value body. Embracing the loss on purpose becomes the engine, which suits a homunculus who has never once known where he is.