Prefaced Insight

Rules clarification for Most Delightful Ponidox: When I say that multiple instances of a character have to interact, that means that each must at least be aware of the other's presence. No looking at the other from Superman's Silver Age time-space telescope or suchlike. Use this handy, dandy group thread if you have further questions.

Comments

[Damaged]

Would electromagnetic force interactions count?

[FanOfMostEverything]

5357010
In most cases, yes. It's rather hard to miss those unless two identical pegasi register on each other's magnetoreception and ignore one another. Whereas, say, sensing visible light reflected off the other character will definitely work. Gravitational interactions, though, those aren't enough by themselves.

[Leafy]

5357010

Would electromagnetic force interactions count?

I don't think so.....

[SockPuppet]

What if the collision is perfectly elastic and momentum and energy are both conserved?

[FanOfMostEverything]

5357027
Hopefully the characters notice and react to bouncing off of one another.

[Damaged]

5357018