The offer is part of the printed card, having a lower right triangular promo on the card front, and the offer explained on the lower half of the card back
During their turn, a player can play an evolution on top of their active Pokmon, put a Pokmon on their bench, play an energy card on a Pokmon, play a supporter/ally or play an item card
Those Exploit Creatures are great here, because in addition to those two (and their card draw), we get a bunch of other effects from them
Dockside Extortionist specifications: Pros Hugely popular for competitive Commander decks Great source of mana for ramp Low mana cost to play Cons Costs an awful lot of money Might make you some enemies at the table Dockside Extortionist is a pirate that Commander players have a lot of strong feelings about
Tamiyo, Inquisitive Student is a one-drop that can block flying creatures safely with her three toughness, creates a Clue token for instant draw later, and flips to a solid counter against mirror matches: her first loyalty ability makes your opponent's army of Deceiver Exarchs into 0/4 creatures that can't kill you through combat damage