This can be achieved by reverting a section of Iocrym.xml to before the "ship explosions rebalance" commit.

https://github.com/INeedAUniqueUsername/Transcendence/commit/26d952017086ba67e0e8adc7a2d2204563311b8b

assumedpseudonym on 12/17/2017 8:14 AM:

 I’m fine with the new plasma effect for most weapons, but I do prefer the old Iocrym weapon effects for their weapons. Besides, the unique appearance drives it home that you’re dealing with something legitimately alien. I heartily +1 this one.

megas on 12/17/2017 2:16 PM:

I like the new flamethrower effect the Fracture Cannon has. Also, the generic plasma explosions are much better than the old line effects that made most of those explosions harmless.

johnbwatson on 12/19/2017 10:31 PM:

I agree with megas. While I'd like a more 'alien' Iocrym, the old line effects look undeniably, well, old. Their new effects could be more unique, but are reasonably distinct and work pretty well.