Hey! No Fair!! You looked in the rulebook!From the PRD:
'Surge (Su): You can call upon your mythic power to overcome difficult challenges. You can expend one use of mythic power to increase any d20 roll you just made by rolling 1d6 and adding it to the result. Using this ability is an immediate action taken after the result of the original roll is revealed. This can change the outcome of the roll. The bonus die gained by using this ability increases to 1d8 at 4th tier, 1d10 at 7th tier, and 1d12 at 10th tier.'
Looks like it is an immediate action after the d20 is rolled.
OOC: Just to respond to Thorn's post, as I went back, the only doors present (that we know of) are the door to the outside and the door in the wall dividing the downstairs. So not only is there not really a door to try the lock on, there is no door to block sound. Is this accurate?
Yes, Thorn went outside, but didn't proceed upstairs. Rather, she loitered near the door to listen for signs Meliara might need help. And I was assuming that she was at the outer doors as well, which I didn't realize were locked but so be it.
Anyway, hopefully we're all on the same page now.