Particles showing up as giant squares in game

[crossmr]

If anyone wants to test this, this is the P_TwinBlast_Primary_MuzzleFlash included with the twinblast paragon character. The particles look fine in the preview, not in the game. Not sure what’s going on here. Other particles I’ve tried to use from paragon characters seem fine.

vs editor preview: There are more than that, it’s just a quick burst and hard to capture it.

How it’s called, same way I’m calling other particle emitters.

[crossmr]

After tracking this down, it seems like there are a few materials with twinblaster that have something wrong with them. I haven’t touched them, but they seem to be fine in the material edit screen, but in content browser (and in other items) those materials just show up as world grid material.