1. Someone's time runs out and their identity is revealed

2. After Hawkmoth's defeat, everyone's finally safe to share their identities, so they all do a big reveal to one another at Esme's place

3. Someone gets caught mid-transformation and their identity is shared on TV

4. You and someone close to you choose to do a reveal to each other (or a one-sided reveal if the other doesn't have a Miraculous)