I don't avoid by breed, but there are several individuals I steer clear of.
1. Brutus, the Rott. He hates King with a passion, and I think King feels the same way after a few run ins. King liked him when he was younger, before he started getting nasty.
2. The little old lady and her JRT. It's known to be a "tough guy", and the woman that owns it is very annoying.
3. Karl, the GSD and his clone son, Klauss, they are so close in appearance it's kind of scary. Klauss is still on the skinny side, but the markings are the same and both of them are agressive towards male dogs.
4. Sandy, the Shar-Pei mix. He's very agressive towards dogs about his size, and King has kind of had it with him. I think those two are now getting to the point that they would really want to go at it, like my last dog and a very large yellow Lab Logan, they wanted to kill each other in their later years, even after both of them were pretty feeble, and Logan had both his hips replaced.
5. Jake, a near clone of King that wants to play, but is so rough that even King gets defensive and wants him to stay away, far away.
6. April, a Greyhound and something mix, she looks like a skinny Lab with odd ears, and hates all male dogs, and stares like she's in a daze, then she starts sneering and drooling. With females, she's great. Molly and her ran into each other at the vets and they played really nice.