Although there is a hand cost, negate & destroy his spell, trap, and monster effects without turn restrictions
Will you be getting this Secret Lair, and if so, which of the cards will you be building Commander decks around
For example, you might combine Bolas's Citadel and Aetherflux Reservoir, giving you card advantage and life to offset the life loss, or maybe have reanimate loops using Chainer, Dementia Master and Gray Merchant of Asphodel
With that, here is a look at the Pokemon Trading Card Game Pocket Cost or Price
Common failure modes include: Generating 83 or 94 cards and calling it a complete deck Including the commander in the 99 rather than the command zone Suggesting cards outside the commander's color identity Listing duplicate cards (violating singleton) Miscounting after you ask for changes ("replace X with Y" sometimes adds both) None of these are edge cases