Obsessed with the pursuit of knowledge above all else, vedalken can appear to be cold and emotionless.

Stoic Rebuttal

Metalcraft — This spell costs {1} less to cast if you control three or more artifacts.
Counter target spell.

Modern Masters 2015

Metalcraft — Stoic Rebuttal costs {1} less to cast if you control three or more artifacts.
Counter target spell.

Duel Decks: Mirrodin Pure vs. New Phyrexia

Scars of Mirrodin

For the purpose of determining whether the cost reduction applies, the number of artifacts you control is checked as you cast Stoic Rebuttal, before your last chance to activate mana abilities to pay for it. For example, if you control three artifacts, you could determine that Stoic Rebuttal costs {U}{U} to cast, then sacrifice one of those artifacts to activate a mana ability.

Stoic Rebuttal’s metalcraft ability functions while Stoic Rebuttal is on the stack.