I'm thinking iterations just confuses things. With a high enough HP value we should be able to eliminate "luck". So here's a pass with 1 iteration and 20 million initial HP:

2: red/blue
8: red/red
13: yellow/blue
13: yellow/red
15: red/yellow
15: yellow/green
17: blue/yellow
17: red/green
17: yellow/yellow
19: blue/red
19: green/blue
19: green/green
19: green/red
19: green/yellow
21: blue/blue
23: blue/green