The On Death trigger works as both a toggle and spawn trigger. This is shared by all the other condition triggers as well, so take note of that.
When Activate Group is disabled, it’ll toggle all objects in its group off.
When Activate Group is enabled, it’ll toggle all objects on. Triggers in the group marked as “Spawn Triggered” will also be activated.
One thing to note is that an On Death trigger can be activated at any time, but its effects will only show up when the player dies. You don’t need to put one on every spike, or something like that.