Stonecoil Serpent

Colorless X-cost creatures were nothing new, but stapling a suite of evergreen keywords onto one and making it an artifact turned a mana sink into a card that slots into any deck regardless of color. The scaling body is the obvious part: pay X, get an X/X with reach and trample that blocks fliers and punches through chump defenders. The quieter piece is protection from multicolored, a clause that reads like flavor filler until you notice how much premium removal and how many bombs live in two or more colors. It ignores an enormous slice of the interaction it would otherwise fear (targeted removal, combat, being enchanted or blocked by gold cards) while staying fully vulnerable to mono-colored answers and, since protection does nothing on the stack, to any counterspell. That seam is deliberate: the ability shields the creature on the battlefield without making it an untargetable brick. Because the counters are placed rather than baked into the printed stats, it feeds counter-specific synergies like doublers and proliferate in ways a static X/X cannot, and being a colorless artifact means the fixing question never arises: no manabase is the wrong one for it. Turn-one one-drop, mid-game bear, late-game finisher, all in a slot that asks nothing of your colors. It is the platonic generically-good card: rarely the most powerful thing in a deck, but the one that fits when nothing else does.