i have no idea how to make a pause system, and i didnt have time to learn on the spot... Also with the boss you just stun it to get some hits and dodge the projectiles. Glad you enjoyed the axe!
i don't know Unity, but in GMS i do in this way : at the beginning of Step Event ( on Update in Unity ) i set an if condition that check for a boolean ( generally a boolean variable of the Main Engine object ) this bool could be named pauseEvent and if is false Update will be skipped
