Knight of the holy Nimbus vs. Training Grounds

[hjalte]

I have a Knight of the Holy Nimbus and a Training Grounds in play.
Can I choose, that it will cost {2} for my opponents to activate knights ability?


[quote="Knight of the Holy Nimbus"]If Knight of the Holy Nimbus would be destroyed, regenerate it.
{2}: Knight of the Holy Nimbus can't be regenerated this turn. Only any opponent may activate this ability.[quote]

From Rize of Eldrazi FAQ:
* You may choose not to apply Training Ground's cost reduction effect. You may also choose to apply only part of it (causing an activated ability of a creature you control to cost just {1} less to activate).

[luma]

The cost reduction is applied by the player, who is activating the ability. Even though it's your Knight and Training Grounds, your opponent gets to choose if he wants to pay {2} or {1}.


601.2e The player [activating the ability] determines the total cost of the spell. -- The total cost is the mana cost or alternative cost (as determined in rule 601.2b), plus all additional costs and cost increases, and minus all cost reductions.

[pi4meterftw]

The cost reduction is applied by the player, who is activating the ability. Even though it's your Knight and Training Grounds, your opponent gets to choose if he wants to pay {2} or {1}.

Why does it say "Determines the total cost of the spell?"

[cdr]

Why does it say "Determines the total cost of the spell?"

Not sure what you mean. The second part of the rule luma quoted defines total cost.