you dont put them in your deck or sideboard
Im quite a fan of Seafloor Oracle on the merits of rate alone as I could see it being an amazing payoff for a Merfolk deck, but Im also skeptical due to the competition it has for the slot it would take up
With the release of nearly every brand-new set, a wide range of legendary creatures are added to Magic, meaning that players are regularly provided with brand-new deck-building options through these new potential commanders
That said, there's a ton of great legendary creatures out there to play as your commander, and while some are pretty obvious, some you might not expect to find
Oubliette-as-a-Room has a different feel from Oubliette as a card
If a creature that regenerates would die, it instead taps, removes all damage from itself, and is removed from combat