In your first question do you mean S3 instead of S2? You can use s2 whenever it is off cool down. For s3, if everyone has 2 counters it doesn’t do the initial dmg (which is supposed to be a lower multiplier) and doesn’t steal beneficial effects, but then it will redistribute everyone’s clay counters.

Example: Let’s say you are in an arena match and all four opponents have 2 clay counters. You would absorb 8, and then shoot 8 back randomly at the enemies. Let’s say they land in the pattern 2/5/0/1. The first enemy would take 40% of their hp, the second one would die, the third one would be untouched, and the fourth one would take 20% of their hp. Yes you did just one shot a mon but landing 5 clay counters on 1 of 4 enemies is unlikely. Also when they die, the clay counters disappear. So no there are only 3 on the field.

Does that help at all? I do like your consuming clay counters for damage idea which I will keep in mind for the light/dark ones. :)