In your typical
multi_manager loop, you set the Multi-threaded flag and have it target whatever is supposed to repeatedly trigger, and after some delay it'll trigger itself.
Triggering the multi_manager again will only create more loops, so instead of a button to start the loop we can use a
trigger_auto to start it from the beginning of the map, and instead of triggering the target directly we can use a
trigger_relay, but we'll leave the relay's target empty to begin with.
To connect the target to the loop, we let the button target a
trigger_changetarget (we can name it
turn_on) to change the relay's target to our
env_blood. We can use another trigger_changetarget (sharing the same name as the first) that will change the button's target to
turn_off.
Now we create another pair of trigger_changetarget, both named
turn_off. One will change the relay's target back to empty, and the other will change the button's target to
turn_on.
It might be a bit complicated, but here's an example map for such a toggled loop:
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