Vannifar, Evolved Enigma

Cloak is what makes both modes here answers to the same question. A face-down permanent enters as a colorless creature with ward, which means the first mode manufactures fodder from your hand while hiding whether that fodder is a mana dork, a finisher, or a blank you had no way to cast yet. The second mode grows every colorless creature you control, and the cloaked bodies the engine keeps producing read as colorless, so they qualify for the counters the same engine hands out. The scaling also reaches whatever else you already run that counts as colorless: artifact creatures, Eldrazi, the odd construct. Both choices trigger after untap but before you declare attackers, so this grows the board the same turn it swings rather than tipping its hand a turn early, and a cloaked creature card unlocks later for its mana cost whenever you want it face up. What the design settles is an old friction: colorless-matters payoffs have historically lived in artifact or Eldrazi shells that compete with green-blue for the same slots. Putting the payoff and the machine that produces its targets on one legendary body means the deck chasing the counters is already the deck making the creatures those counters land on. It reframes green-blue's usual value plan (card advantage, tempo, incremental growth) around bodies that arrive concealed and get bigger before anyone learns what they are.