There are 25 merfolk in the deck, five lords, and countless others that distribute counters to themselves and others
Overall they seem to be priced appropriately, but a few stand out as interesting to me
Full master set checklist every card in the OP13 set
Tibalt, Cosmic Impostor As Tibalt enters the battlefield, you get an emblem with "You may play cards exiled with Tibalt, Cosmic Impostor, and you may spend mana as though it were mana of any color to cast those spells." [+2]: Exile the top card of each player's library
punch spells require a strong creature
Wizards experimented with 'symmetric draw' with cards like Secret Rendezvous, where you and another player could both draw cards, but giving your opponent an advantage for something they could probably do themselves feels like a much bigger drawback than other colors