Devastation tier bonus

A quick question. I tried to use a dummy to get some ideas but wasn’t getting able to see how Obsidian Shards actually function. Does it behave like Hunter’s Marksmanship “Master Marksman” talent where each damage applies a ‘stack’ behind the scene? Or is it a single debuff that only refreshes? It seems like the former but without any info on the tier set asides what it tells it does, it kind of leaves a lot in the air.

Just curious, just happy enough to get my Evoker a tier bonus at last.

I don’t believe master marksman applies a “stack” behind the scene, but rather its a singular debuff and everytime it is refreshed, the damage left over is rolled into the new dot. This is also how devastation tier works, and I’m pretty sure the majority of dots in the game. Albeit with most other dots, it won’t roll the entire damage left unapplied, but rather only a few ticks.

It does the ignite mechanic. The damage keeps rolling over. Think of the set bonus as just a delayed 12% buff to your spenders.