Highlander became Commander. There are only a couple extra rules. In human speak: 1. cards in your deck (100 total including the commander) have to be the same

Highlander became Commander. There are only a couple extra rules. In human speak: 1. cards in your deck (100 total including the commander) have to be the same colors as your commander. 2. you start at 40 life and a commander in your command zone. 3. if your commander goes to the graveyard or exile, put him back in the command zone, but he costs 2 more colorless to cast each time this happens. 4. if a commander personally deals 21 damage to someone, they lose. If they insisted on one card, they were playing commander or brawl (MTG's new "commander lite" using 60 cards, standard only with slightly different life rules).