This is a trait in Enemies Beyond for all Tzeentch daemons giving a Force Field of 20 and Overloads on an 8 on a die. Now how does the daemon "repair" it? Normally it is a Very Hard Tech-Use test but seems...stupid for a daemon. I didn't see anything anywhere else in Enemies Beyond nor anything in the FAQ.

Maybe a Very Hard Willpower test?

~ alemander

Why is a demon enough of a recurring or semi permanent character that he can't just do it offscreen between encounters.

I was always of the opinion you really couldn't fix a forcefield DURING a firefight anyway.

It was during a battle. I didn't get the sense that a Force Field couldn't be repaired, although the Very Hard nature of the test does lend to that. It doesn't say that it can't be during tactical time.

~ alemander

The entry for Tech-Use in the core rulebook says that a skill test takes "1 minute, or more for complex systems." If a Daemon took that much time to fix anything, they would vanish from realspace due to Warp Instability. Not that your players would mind, of course

For practical purposes, I'd rule that the daemon's force field doesn't work until the end of the encounter (after which either the daemon or the party is very likely dead).

I don't think that the force field "breaks" and needs to be "repaired" - it is Warp Energy, after all. But I would agree that there must be some drawback to an overload, or else FFG wouldn't have given it an overload possibility. Maybe treat it like an AdMech luminen shield where it takes a Reaction to raise the shield?