Cthulhu's Abyssal Gift

You conjure a gift from the depths. You gain the following benefits for the duration of the spell:

• You can breathe underwater and gain a swimming and flying speed equal to twice your movement speed.
• You gain immunity to psychic damage.
• You gain an additional bonus to your armor class equal to your spellcasting ability modifier.
• Spell attack rolls you make are at advantage.
• Whenever you cast Eldritch Blast, you deal an additional 2d8 cold or psychic damage (your choice).