Two-Face

When attacking (after attack is declared but before blockers are declared) roll 1d6. If 1-3 are rolled, Two-Face can not attack and is returned to your hand. If 4-6 is rolled, add a +1/+1 counter to Two-Face and proceed with the attack.
"Why are we doing this? Because we are now two faces. One good, the other bad. Half-and-half. Fifty fifty. Opposite and equal. And we're deadlocked.
When that happens... we let the coin decide."