Cast

Cast is a keyword action. It was introduced in Alpha but temporary replaced with Play in the Sixth Edition rules changes and then reinstated in Magic 2010. When you cast a spell, you take it from where it is (usually the hand), put it on the stack, and pay its costs, so that it will eventually resolve and have its effect.

"When you cast"
A few cards have abilities that trigger when they are cast, as opposed to when they enter the battlefield. This means that countering the spell will not prevent the triggered ability from occurring. Likewise, countering the ability will not prevent the spell from resolving. Cascade, replicate, and storm are all triggered abilities that trigger when the spell with them is cast. Abilities triggered that way are put on stack above the spell, meaning that the abilites resolve before the spell does. Many Eldrazi cards also feature abilities that trigger when they’re cast.

Rules
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