Prismatic Omen

Two mana to make every land you control answer to every name at once: this is type-laundering as an enchantment, and the consequences run deeper than fixing. The obvious read is that it untaps your colors, turning a single Forest into a source of all five, which is real but the least interesting thing it does. The payoff lives in cards that count basic land types rather than tap for mana. Valakut, the Molten Pinnacle reads each of your lands as a Mountain, so every land drop after the enabler becomes a Valakut trigger, collapsing a slow combo into a fast one. Domain spells see five types where there was one. The line that makes it dangerous is that it touches lands you control with no clause for what those lands are: nonbasics, manlands, and utility lands all gain the full slate, which is why it anchors a degenerate land-matters engine rather than just a five-color rock. The cost it pays for all this is fragility: with no lands on the table it has nothing to rewrite, it folds to enchantment removal, and it adds zero lands of its own, so it only ever multiplies what you already have. That is the trade a type-changer makes. It does not generate value; it reinterprets the value already on the table, and the ceiling depends entirely on how many other cards you have asked to read the land types it rewrites.