If I cast mental binding on a target that already has the paralyzed effect from a previous mental binding, there's a rather high chance that when the duration of the first ends the target will have the second paralyzed effect appear on their status list, but will still move and attack as if they didn't.

Unfortunately, this is working as intended: two debuffs of the same group do not stack. The status monitor showing the second non-functional debuff is actually the bug here, not the other way round.

Edited May 8, 201510 yr by Zwiebelchen

Shouldn't it replace the previous debuff? So you can reapply a debuff before the previous one runs out.

I guess they wanted to avoid "stun-locking."

Then they should use diminishing returns, or at least warn you that reapplied spells don't prolong duration.

Edited May 8, 201510 yr by LeonKowalski

Yeah, as it is, if the second paralyse lands 0.1 second before the first expires it does nothing, but if it lands 0.1 second after the first expires then it works fully, it's just so super weird and unexpected, especially since the status shows the second one as active even if it is not.