If, during your declare attackers step, Deathbellow Raider is tapped, is affected by a spell or ability that says it can't attack, or hasn't been under your control continuously since the turn began (and doesn't have haste), then it doesn't attack. If there's a cost associated with having a creature attack, you're not forced to pay that cost, so it doesn't have to attack in that case either.
15-09-2013
wotc
You still choose which player or planeswalker Deathbellow Raider attacks.
Random a card of Magic: The Gathering (MTG), but you can also roll the D20 dice, random a Planeswalker, have fun with the random rules and more.
: Regenerate Deathbellow Raider.
Wayne Reynolds2013-09-27
