What should I do if I do the 4 horse game
You won't always get the 4 knights.
1) Many don't play 1...e5.
2) For those that do, many play the three knights. Either 1.e4 e5 2.Nf3 Nc6 3.Nc3 g6 or 1.e4 e5 2.Nf3 Nf6 3.Nc3 Bb4.
I'm not certain I understand the question, but if you play the Four Knights with white then just play 4. Bb5
This is really a great, solid opening for white. I sometimes wonder why it's not seen more at the top level. I'm guessing it's just considered a little too drawish.