Zohah, the Ogdoadic Boundless — Ruling

Effetto 1

The effect that makes your opponent draw a card, adds an "Abhyss" monster from your Deck to your hand, and has each player send a card from their hand to the Graveyard is a Trigger Effect. (This effect can be activated in the Graveyard if this card is sent from the field to the Graveyard, or on the field when this card is Special Summoned from the Graveyard. It can also be activated during the Damage Step.)
Your opponent drawing a card and you adding an "Abhyss" monster from your Deck to your hand occur simultaneously. However, these actions are not simultaneous with each player sending a card from their hand to the Graveyard.

The effect that adds this card to your hand is an Ignition Effect that can be activated in the Graveyard. (Send 1 card from your hand to the Graveyard as the cost of activating this effect.)