When your opponent activates “Huge Revolution” while your “Pandemonium Watchbear” is on your side of the field, your “Pandemonium” will not be destroyed.
When your “Pandemonium” is going to be destroyed by “Mystical Space Typhoon”, you can chain “Ceasefire” to flip your “Pandemonium Watchbear” face-up, and “Pandemonium” will not be destroyed.
Netrep Rulings:
If a Field Spell Card is played while “Pandemonium” is active, “Pandemonium” is destroyed, even if “Pandemonium Watchbear” is on the field.