Aven Trailblazer

Domain attaches itself to toughness here, not power, and that choice decides everything about what this Bird is for. The count of basic land types among your lands sets its toughness, so a single type leaves a fragile 2/1 while a full five-type spread props it up to a 2/5: the clock never moves, only the durability. The effect is a flying blocker that grows harder to remove as your manabase commits, an evasive wall whose staying power reads back exactly how many colors you assembled. That makes it a defensive piece rather than a threat, something to hold a board with while the toughness shrugs off removal aimed at two-power bodies. The dependency runs both directions, though: anything that strips your nonbasics or homogenizes your lands collapses the toughness on the spot, and a color-screwed board can sink the creature all the way to a 2/0. This is domain at its gentlest. No card advantage, no removal stapled on, no graveyard hook, just a stat tied to how greedy you were with your fixing. Among the domain creatures that ask you to earn the payoff through deckbuilding rather than handing it over for free, this one sits near the bottom of the ladder: a modest reward for spreading your lands across all five basic types.