Wax-Wane Witness
Read literally, the pump condition is far broader than the Bat-and-Cleric typing suggests: not just lifegain, but any life change during your turn, up or down, feeds the +1/+0. Fetch-style life payments, shocklands, phyrexian costs, and self-inflicted damage all count as fuel, which quietly hands an incremental lifegain shell an aggressive angle it was not necessarily built to want. The pump is deliberately narrow, and that narrowness is the balancing lever: it caps at power alone, resets at end of turn, and only fires on your own turn. So the growth is a single-turn threat rather than a permanent one. On your combat step, this can present a much larger body than an opponent can plan around; on their turn, it reverts to a 2/4 flier that mostly blocks. That timing restriction keeps the creature from spiraling: it can spike for one attack, but it never carries the accumulated size forward. The flying and vigilance are the connective tissue, letting it swing into an open board and still hold ground, which matters more for a creature whose power is a moving target than for a static beater. It rewards decks already committed to churning their own life total, and asks nothing extra of decks that were going to pay life anyway.
