As part of the resolution of my Flash, I put Nyxbloom Ancient onto the battlefield. Can I now tap lands for extra mana to pay for the remaining 2GGG? Can I tap my lands for the extra mana AND then choose not to pay any of it, sacrificing Ancient as a sort of one-shot Ritual?Comp Rules wrote:608.2f If an effect gives a player the option to pay mana, they may activate mana abilities before taking that action.
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No other spells can normally be cast and no other abilities can normally be activated during resolution.
If I already have the Monarch status, does the above change at all if I replace Ancient with Regal Behemoth? Meaning, is there any difference between replacement effects that modify mana being added (Ancient) and triggered mana abilities (Behemoth), that would change the answer to the above questions?