Decoy

Codex Entry:

 * If Decoy is destroyed while still unrevealed (e.g. by a Seeking Dispel), its controller still gains the 2 mana.
 * If Decoy is countered (e.g. by Nullify), its controller does not gain the 2 mana, because the enchantment never resolved to have its effect.
 * If Decoy is discarded from somewhere other than play, such as if it had been planned to be cast with a familiar which then is destroyed, it does not gain its owner 2 mana.