Lorthos, Tentacled Terror is a rare Legendary Creature — Octopus card from Unknown Event (UNK), collector number RU08a. Current market price: $22.99, TCGplayer market prices via Scryfall.
Mono Eminence — As the game begins, if Lorthos is your commander and your deck's color identity is mono-blue, your starting hand size becomes 8. (You draw 8 cards and your maximum hand size is 8.) Whenever Lorthos attacks, tap all permanents your opponent controls. Partner (You can have two commanders if both have partner.)