Earnest Fellowship

Protection is a four-part keyword (can't be damaged, enchanted, blocked, or targeted by sources of the named quality), and here it gets pointed inward in the strangest possible way: a creature gains protection from its own colors. A white creature can't be targeted by white spells. A red creature can't be blocked by red creatures. The symmetry cuts every direction at once, which turns this into less a build-around than a puzzle box. The obvious reading is a removal-proofing enchantment: opponents can no longer point their on-color removal at your matching creatures, and color-based combat math collapses into a stalemate where same-color creatures simply pass through each other. But the same clause shuts off half of white's and green's own toolkits (your white auras and white-source pump won't stick to white creatures), so the card punishes the unwary as readily as it protects the prepared. Colorless creatures, having no colors to gain protection from, are untouched by it entirely, which is the seam most enabling builds aim at: the asymmetry between mono-color boards and colorless ones is where the deckbuilding actually happens. An early-era static effect of the total-symmetry school, printed as a single sentence and left for players to untangle: one line that rewrites the rules of combat and targeting for every creature in play, friend and foe, and asks you to be the one who already knew where the exceptions lay.