Serial Escalation/Theatre

A common Improv game is called "Yes, And" fits this trope. Someone says something mundane, and someone else adds "Yes, and...!" attempting to top the person who spoke before them. If it doesn't end with a ridiculous Evil Plan to Take Over the World, someone wasn't playing correctly.
- Actually, that's an Improv technique. You confirm a person's plan and then add onto it. "Let's go to the park!" "Yes, and then we can feed the ducks!" And then it will get crazy.
- Improv in general tends towards this by design; the cardinal rule of improv is to never say no to your partner (otherwise the scene loses momentum fast). "Yes, And" simply turns it Up to Eleven.