Gladehart Cavalry

When Gladehart Cavalry enters, support 6. (Put a +1/+1 counter on each of up to six other target creatures.)
Whenever a creature you control with a +1/+1 counter on it dies, you gain 2 life.

Duel Decks: Elves vs. Inventors

When Gladehart Cavalry enters the battlefield, support 6. (Put a +1/+1 counter on each of up to six other target creatures.)
Whenever a creature you control with a +1/+1 counter on it dies, you gain 2 life.

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You can’t put more than one +1/+1 counter on any one target using the support action.

You gain 2 life per creature, not per +1/+1 counter.

If a spell with support has other abilities that target creatures, those abilities and the support ability can target the same creature.

Support can target a creature you don’t control.

If Gladehart Cavalry dies at the same time as a creature you control with a +1/+1 counter on it, its ability will trigger.

If Gladehart Cavalry somehow gets a +1/+1 counter, it dying will cause its own ability to trigger.