text: Heart-Piercer Manticore features a new style of triggered ability. When it enters the battlefield, its triggered ability goes on the stack without a target. While that ability is resolving, you may sacrifice a creature. If you do, a second ability triggers and you pick a target that will be dealt damage. This is different from other abilities that say "If you do . . ." in that players may cast spells and activate abilities before a creature is sacrificed and then again after the creature is sacrificed but before damage is dealt.