There's a Hole in Catacomb Carnage visible only from certain angles

[Purkkaviritys]

So yeah, I found this during previous weekend...

[Knightmare66]

That's a minor VIS error, the sort that occur during compilation. There isn't much that can be done about it, except making the surrounding brushes detail. And that outcropping is already a detail brush.

There's a similar issue near the start of e3m5 I recently fixed that was due to spiral stairs not being detail.

[Martin Müller]

Speaking about holes...

e1dm2a above the first spawn area, you can rocket/shotcycler jump out of it and go out to the outside area.