Allow you to stack poison multiple times up to +2 with Venom Injection only.
You can inflict other poison such as Poison Dagger/Draconic Charge/etc. for initial/first poison(+0), but only Venom Injection can stack poison on top(poison+0 into +1 then +1 into +2)!!. Their chance are dependant on this skill level:. Poison+1 chance is (25 + Skill Level * 5)% of Final Poison+0 Chance(Venom Inject). Poison+2 chance is (Skill Level * 5)% of Final Poison+0 Chance(Venom Inject). About Poison duration… it will be extended by +10s everytime you successfully inflict Poison+1 or Poison+2.. If a target has Poison+1 or Poison+2, then attacking that target will automatically inflict poison damage(even other players/merc/pets can inflict poison damage). But this poison can only be inflicted/triggered once at max every 1 second. This means, doing multi hit skill won’t trigger this poison multiple times in 1 second, even if you and your allies hit at same time still trigger once!
altho, it is possible to get multiple poison in 1 second. But only achievable with every time enemies attack!. FYI, About poison damage from this skill.. Poison dmg = dex scale + (Atk+matk) scale Poison+1 dmg = dex scale + 2 * (Atk+matk) scale Poison+2 dmg = dex scale + 3 * (Atk+matk) scale You can check full meth in #ailment-information