Siphon mastery - How mastery increases

Obito0099

Do I think right the Mastery grows like this:
GL Kylo has 45 Mastery, i use strike, then my Siphon is 40, i use aoe then mastery equals 45 + 40% of 45 = 65,25. And then i use strike, my Siphon is 80, is use aoe then mastery equals 65,25 + 80% of 65,25 (current value) or 65,25 + 80% 45 (initial value)?

KausDebonair

I believe it stacks. For easy math, let’s say SLKR has 100 mastery. Poke for 40 siphon, then AoE gives you 140 mastery. Poke again to get to 80 siphon, then AoE again brings mastery to 252 (140+(140*.8)). The stacking is what lets SLKR get to millions of damage on his basic in the Sith raid.

Ultra

Correct, mastery gain is based on current stacked value