fading quartz
https://www.twitch.tv/bunzine/clip/ProudHandsomeLeopardBabyRage-VgVRXUYCcMCdZp5r
There seems to be a bug where the player is not granted immunity while teleporting to the boss area. In my case, I died just before teleporting. In the clip, you can see that I die, then get teleported (apparently alive again), but I immediately die again upon arrival.
old girder
This can happen at any transition where you leave an area with enemies present.
The moment you start the transition by interacting with the gate/border/etc. you should become invincible and this should be revoked the moment the load completes.
Also the inputs should be locked while in this invincibility phase. I could walk half the screen after interacting, moving into a new enemy pack. This might happen unintended.