Whenever you
castTo cast a spell is to take it from the zone it’s in (usually the hand), put it on the stack, and pay its costs, so that it will eventually resolve and have its effect. A player may cast a spell if they have priority. See rule 601, “Casting Spells.”
To cast a card is to cast it as a spell. (CR 701.5) an instant or sorcery spell,
surveilTo “surveil N” means to look at the top N cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.
If an effect allows you to look at additional cards while you surveil, those cards are included among the cards you may put into your graveyard and on top of your library in any order.
If a player is instructed to surveil 0, no surveil event occurs. Abilities that trigger whenever a player surveils won’t trigger.
An ability that triggers whenever a player surveils triggers after the process described in rule 701.25a is complete, even if some or all of those actions were impossible. (CR 701.25) 1.
At the beginning of your end step, each opponent may
sacrificeTo sacrifice a permanent, its controller moves it from the battlefield directly to its owner’s graveyard. A player can’t sacrifice something that isn’t a permanent, or something that’s a permanent they don’t control. Sacrificing a permanent doesn’t destroy it, so regeneration or other effects that replace destruction can’t affect this action. (CR 701.21) a nontoken creature of their choice. Each opponent who doesn't loses 2 life for each instant and sorcery card in your graveyard.