Degen question

If two people use the same skills lets say Burning arrow and hit the target will the degen be doubled? As I heard it only goes to -10 degen so would it make any difference or would it just cancel it out or something? Same thing with other degen spells like life siphon etc.

Same effects don't stack.

If two people apply burning, that's only 1 burning condition. Different conditions and hexes do stack. If you apply poison, burning and bleeding, they all stack. If you apply 3 different burning skills, that's still only 1 condition. It depends a bit on the situations which one prevails though.

Degen is capped though.

Oh ok makes some sense lol, but lets say ones using burning arrow and poision while the toher is using burning arrow and barbed so the burning won't stack but will the degen add up after 10? Becuse thast -14 degen lol.

Yes.
He'll be burning, poisioned, and bleeding.
He will have "-14" degen, but will only really be suffering -10.

However, say the target has some sort of regeneration from a spell (like +5 regen). Instead of suffering from -5 degen (-10 + 5), he'll suffer from -9 degen (-14 + 5).

True, degen is capped at 10, but that extra 4 doesn't just disappear. That extra degen comes into play if someone uses a skill like [skill]Troll Unguent[/skill] or [skill]Healing Breeze[/skill]. If Troll Unguent gives you 6 regen for example, the degen on that person will be 8, not 4 (14-6=8). I hope that makes sense.

EDIT: Hawk beat me to it