Ava, The Faithless

Partner with Zealot, Faithful Demon
(When this creature enters the battlefield, target player
may put Zealot into their hand from their library, then
shuffle.)
When a creature you control dies draw a card.
Sacrifice a creature: add {w},{b},or {r} to your mana
pool.
Sacrifice ten non token creatures: get an emblem saying "If a creature dying would trigger an
ability of a permanent you control, that ability triggers two additional times."