(Misdiagnosis? shame )
I believe this is an intentional script-related event, rather than a bug.

There's a story script file called "RC_DW_Arena.txt" that holds all the Driftwood-related arena events (RC_DW stands for Reaper's Coast - Driftwood).

Unless I'm mistaken, this bit concerns the void monster you're referring to:

Code
IF
ObjectEnteredCombat(CHARACTERGUID_S_RC_DW_UnderTavern_Voidwoken_13bb467b-de20-4726-8afd-757705352361,_)
AND
IsInArena(CHARACTERGUID_S_RC_DW_UnderTavern_Voidwoken_13bb467b-de20-4726-8afd-757705352361,1)
AND
QueryOnlyOnce("RC_DW_UnderTavern_Voidwoken_JumpToTurn")
THEN
SetOnStage(ITEMGUID_S_RC_DW_UnderTavern_Voidwoken_ObjHelper_c0e93fcf-4dae-48e8-a278-66393b206708,0);
JumpToTurn(CHARACTERGUID_S_RC_DW_UnderTavern_Voidwoken_13bb467b-de20-4726-8afd-757705352361);


The part that specifically makes the fight skip your character's initiative advantage is this function:
Code
JumpToTurn(CHARACTERGUID_S_RC_DW_UnderTavern_Voidwoken_13bb467b-de20-4726-8afd-757705352361);

So, unsolicited code aside, you can see that this isn't really a bug, but an intended action for this fight.

The good news is it's entirely possible to change it with a mod.

Edit: Ah, I missed this bit:
Originally Posted by Av4lan
and from then on, ALL MY CHARACTER TURNS ARE BEING SKIPPED!


Apologies. Lack of sleep and all that. sleep
Some information that may help Larian: Was this a more recent save (i.e., from the latest patch or two), or is this from a much older save?

Last edited by LaughingLeader; 08/06/18 08:29 AM.
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