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I am currently playing a Warlock and I am going to take the tome pact boon. I know you cannot be concentrating on two spells at once but if I am concentrating on Hex and I cast guidance immediately before an ability check (same round) would Hex end? It is six seconds or less that guidance would be up. Is that enough time for Hex to end? Could it be considered instantaneous in this case? I guess my main question is could I cast guidance immediately before a check and keep Hex active?