Twins of Discord
From Modern Horizons 3 Commander set
Twins of Discord
Creature — Eldrazi
8/6
Whenever you attack, choose odd or even. Creatures with mana value of that quality can't block this turn. (Zero is even.)
Each other colorless creature you control has bloodthirst 2. (If an opponent was dealt damage this turn, that creature enters with two additional +1/+1 counters on it.)
Rulings
- The mana value of a face-down creature is 0.
- The mana value of a token that isn't a copy of another object is 0.
- If a creature on the battlefield has in its mana cost, X is 0 when determining its mana value.
- Multiple instances of bloodthirst are cumulative. For example, if you control Twins of Discord and a colorless creature with bloodthirst 1 enters the battlefield under your control, that creature will enter the battlefield with three +1/+1 counters on it if an opponent has been dealt damage that turn.