Whenever Arabella attacks, it deals X damage to each opponent and you gain X life, where X is the number of creatures you control with power 2 or less.

Creatures you control with power 2 or less can't be blocked by creatures with power 3 or greater. If an ability of a creature you control with power 2 or less triggers, that ability triggers an additional time.

Lifelink Whenever one or more other creatures you control with power 2 or less enter, draw a card. This ability triggers only once each turn. When Enduring Innocence dies, if it was a creature, return it to the battlefield under its owner's control. It's an enchantment. (It's not a creature.)

Grenzo enters with X +1/+1 counters on it. {2}: Put the bottom card of your library into your graveyard. If it's a creature card with power less than or equal to Grenzo's power, put it onto the battlefield.