The official rules for the amplify ability are as follows:502.27. Amplify* The player who will control the creature is the one who reveals the cards.
502.27a Amplify is a static ability. "Amplify [X]" means "As this card comes into play, reveal any number of cards from your hand that share a creature type with this card. This card comes into play with X +1/+1 counters on it for each card revealed this way. You can't reveal this card or any other cards that are coming into play at the same time as this card."
502.27b If a creature has multiple instances of amplify, each one works separately.
* Each revealed card must share a creature type with the amplify card. The reminder text reminds you what those types are.
* Playing the Onslaught™ card Artificial Evolution on an amplify spell on the stack can change what types need to be revealed. The card Conspiracy can also change what types need to be revealed.
* If multiple creatures with amplify are going to come into play under your control at the same time, you're allowed to reveal the same cards for each of them.
* If you play Clone and choose for it to copy a creature with amplify, you get to reveal cards and get +1/+1 counters.
The official rules for the double-strike ability and updated rules for the first-strike ability are as follows:502.28 Double Strike* Double strike isn't first strike. Effects that make a creature lose first strike won't make it lose double strike.
502.28a Double strike is a static ability that modifies the rules for the combat damage step.
502.28b During the combat damage step, if at least one attacking or blocking creature has double strike or first strike, creatures without double strike or first strike (see rule 502.2) don't assign combat damage. Instead of proceeding to end of combat, the phase gets a second combat damage step to handle the remaining creatures. Creatures with double strike also assign combat damage during the second combat damage step.
502.28c Removing double strike from a creature during the first combat damage step will stop it from assigning combat damage in the second combat damage step.
502.28d Giving double strike to a creature after combat damage has been put onto the stack in the first combat damage step will allow the creature to assign combat damage in the second combat damage step, even if it already assigned combat damage in the first combat damage step.
502.28e Multiple instances of double strike on the same creature are redundant.
502.2. First Strike
502.2a First strike is a static ability that modifies the rules for the combat damage step.
502.2b During the combat damage step, if at least one attacking or blocking creature has first strike or double strike, creatures without first strike or double strike (see rule 502.28) don't assign combat damage. Instead of proceeding to end of combat, the phase gets a second combat damage step to handle the remaining creatures.
502.2c Adding or removing first strike after the first combat damage step won't prevent a creature from dealing combat damage or allow it to deal combat damage twice.
502.2d Multiple instances of first strike on the same creature are redundant.
* Creatures with double strike and creatures with first strike deal combat damage in the first combat damage step.
* All creatures that didn't assign combat damage in the first combat damage step assign combat damage in the second combat damage step. In addition, all creatures with double strike assign combat damage again in the second step.
* If a creature has both double strike and trample, the combat damage it assigned during the first combat damage step will be considered when determining how much damage can trample through in the second combat damage step.
The official rules for the provoke ability are as follows:502.29. Provoke* There's no requirement for the provoked creature to be tapped or to be able to block.
502.29a Provoke is a triggered ability. "Provoke" means "Whenever this creature attacks, you may choose to have target creature defending player controls block this creature this combat if able. If you do, untap that creature."
502.29b If a creature has multiple instances of provoke, each triggers separately.
* You can choose not to force the creature to block, in which case it won't untap.
* If the provoked creature becomes tapped before the declare blockers step, it won't be able to block.
* If a creature is provoked by more than one creature, the controller of the provoked creature chooses which one it blocks.
* If the provoked creature has any costs to block, those costs don't have to be paid. If the costs are paid, the provoked creature must block the creature with provoke.
See the Onslaught FAQ for information about the morph ability.
Morph Triggered Abilities
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