How do I Stop All Other Events midway throu when a Boss Dies

Say I am using a big long event like the following to cycle through a boss phase:

Event: Do boss cycle is True

Action: Set Do boss cycle false

Action: walk left for a bit

Action: wait 3 seconds

Action: shoot a fireball

Action: wait 5 seconds

Action: shoot lightning

Action: wait 10 seconds

Action: Set Do boss cycle True

Say the boss died around the part where its shooting a fireball. I want to end the event then. Currently it will continue on and play the sound effect (really the only problem since i destroy the actual boss). So you'll be doing your victory dance while your hearing lighting being shot (or more annoying the screen shaking...).

Any advice?

Create a global varialble like BossAlive. Set it to 1 when the boss dies. Put all your events you want to stop under Condition -> 'BossAlive = 0' -> ...Rest of your events

Or you could put them in a group and activate/deactivate the group as needed.