Are there any other things that happen on uneven turn numbers that should disrupt a counter?
Because I can see something like this (which is heavily inspired by the conversation so far):
Ctrl+Wait - Wait until the next spawn cycle
Alt+Wait - Wait for 5 turns (should it also stop on the next spawn cycle?)
Ctrl+Alt+Wait - Wait for the next significant event, if it can happen. Caveat - there is no good way to detect if briar can ever grow, so it would have to either be interruptable or would have an upper limit of, say, 100 turns.
At the same time I don't care about the briar thing, implementing it will be a slight pain so if no one cares much I'd just happily throw it out the window.
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