Boo, Resident Spook (Yellow)

Spellvoid does not go on the chain as it is not a trigger. It is a replacement effect. There is no time to respond after the decision to destroy the card and prevent that damage.

Spellvoid is optional. You choose whether to use spellvoid or not at the time the arcane damage resolves.

If a card has Spellvoid 2 but only prevents 1 arcane damage, there will not be a leftover prevention shield. Note: It can only defend arcane damage from a single source, Spellvoid 2 cannot prevent one arcane damage each from two different sources.

Spellvoid does not go on the chain as it is not a trigger. It is a replacement effect. There is no opportunity to respond after the decision to destroy the card and prevent that damage.

If a card dealing arcane damage is fully prevented by spellvoid (Or in conjunction with other preventions) it would not be considered to have dealt arcane damage and would not trigger effects that rely on arcane damage being dealt.

Watery Grave is an ability keyword.

Watery Grave is a trigger that ONLY triggers if the card is put from the arena into the graveyard, excluding when it is a non-permanent defending card on the combat chain. It also does not trigger if it is put into the graveyard by other means (e.g. discarded from your hand, destroyed from the top of the deck, put into the graveyard from your deck).

When Watery Grave’s triggered effect resolves, you must turn that card with watery grave face-down in your graveyard.

Similar to face-down cards in the banish zone, you can look at face-down cards in your graveyard. Opponents cannot look at face-down cards in your graveyard.

Cards and effects that interact with cards in the graveyard cannot interact with face-down cards in the graveyard unless the effect specifies that it affects face-down cards. For example, if a card requires you to banish 3 random cards from your graveyard as an additional cost, face-down banished cards are unable to be banished from your graveyard this way to pay for the cost.