Xythera, Grave Nexus

Grave Nexus: As long as Xythera, Grave Nexus is
in your command zone, Whenever a creature enters the battlefield from your graveyard, target opponent loses 2 life and you scry 2.

Soul Tether: Whenever a card is exiled from your graveyard, you may gain 2 life (Creatures with Soul Tether have abilities from the graveyard.)

Battlefield: Whenever a creature you control dies,
you may draw a card.