Threads of Disloyalty

Enchantment - Aura

Enchant creature with mana value 2 or less
You control enchanted creature.

"Over time, Konda grew ever more suspicious, fearing even his most loyal allies were being manipulated by unseen hands."
—The History of Kamigawa

2005-02-01 Creatures on the battlefield treat {X} in their mana cost as 0 for the purposes of calculating converted mana costs.
2005-02-01 Threads of Disloyalty can't target a creature with converted mana cost 3 or greater. If it somehow enchants a creature with converted mana cost 3 or greater, Threads of Disloyalty is put into the graveyard the next time state-based actions are checked.
2005-02-01 Tokens usually have a converted mana cost of 0.

Card is in preconstructed decks:

mtg.wtf