Azurill

Protection from Spirits.
Azurill gets +1/+0 as long as you control another creature.
Whenever Azurill deals damage to a permanent or player, it deals that much damage plus 1 to that permanent or player instead.
{2}, {t}: Sacrifice Azurill, search your library for a blue Fairy Mouse enchantment creature card with converted mana cost 5 or less, put it on the battlefield tapped, then shuffle your library.