Diamond Mare

A 1/3 body that taxes nothing and asks nothing: choose a color on entry, then bank a life every time you cast a spell of that color. The design is built entirely around incidental lifegain, and the choice of color rather than a fixed one is what lets it slot into any deck without bending the spell base around it. In a token-light, spell-dense shell it ticks up steadily over a turn cycle, doing the slow attrition work that one-shot lifegain spells cannot: the value scales with how often you already cast spells, not with any commitment you make to the artifact itself. The toughness is the operative number here, surviving the small-ball aggression and incidental pings that the card is positioned against, so it sticks around long enough for the trigger to matter. It is colorless to cast and an artifact in type, which means it draws from any deck regardless of its own color identity, a quiet bit of flexibility that mono-color and two-color builds both lean on. This is lifegain-as-engine rather than lifegain-as-burst, and the modesty is the point: it never threatens the board, it just refuses to let an aggressive opponent's math stay clean.