Does kicker count as part of the spell's converted mana cost for effects that care about mana value?

A spell's mana value (formerly called converted mana cost) is determined exclusively by the mana symbols printed in its mana cost, as defined by CR 202.3. Additional costs — including kicker — are never part of the mana cost and therefore never change the mana value of the spell, whether on the stack or anywhere else.

Kicker is defined under CR 702.33 as an optional additional cost. When you pay kicker, you are paying more to cast the spell, but the spell's mana cost itself is unchanged. Effects that ask "what is this spell's mana value?" always look at the printed mana cost, ignoring any additional costs paid.

This matters for effects like Mystical Dispute (counter unless they pay 2 more if the spell's mana value is 3 or less), cost-reduction effects, or "if a spell with mana value X" triggers. None of these are affected by whether kicker was paid.

Example: You cast Inscription of Ruin with kicker, paying a total of 8 mana (2B base + 5 kicker). Its mana value on the stack is still 3 (the converted cost of 2B). An opponent's Spell Snare, which counters spells with mana value 2, cannot counter it — but the kicker payment didn't change that; it still only misses because the mana value is 3, not 2.

The only exception to mana value calculations involves X in a mana cost (CR 202.3b): if X is part of the printed mana cost, it counts as whatever value was chosen. But kicker is never part of the printed mana cost, so it is always ignored entirely.