First sun choke you ever land is: 10% *
Second sun choke you land: 16% *
Third sun choke you land : 19% *
As you can see, this is a stacking method for a total of three, let's call them Sun Stacks, for Kotal.
By inputting sun scorch (FDB+1) he will consume however many stacks Kotal has for super meter.
1 sun stack = some meter
2 sun stacks = more meter
3 sun stacks = even more meter
You can also EX sun scorch to regain a small amount of health and the principles are the same as the normal sun scorch, but with health instead of meter. The larger your stacks the more health.
These stacks are not on a time limit and you do not lose them from being hit or if the round ends.
EX sun choke has nothing to do with damage; the move only provides armor.
* I am not sure on the exact percents, but I believe those are close.
Osh-Tekk Edit: If you are having trouble understanding this concept hop into training mode and try it yourself. Be sure not to hit the "select" button to reset practice or you will lose all your stacks.