What is this effect/vst???

[E5K1M0]

Hai guise. So, before anyone drills me for not "searching", I've been trying to find this effect/vst for month's to no avail. Mainly because I don't know what the hell keywords to search for. But basically, I'm trying to find the effect in the very beginning of this track... ........ It almost sounds like it's underwater, then transitions to a normal sound. Any help will be greatly appreciated.

 

[Chainsaw Calligraphy]

That's just a low pass filter automated to sweep upwards. This is my go to LPF:
http://www.gvst.co.uk/glow.htm

EDIT: Don't forget to turn up the resonance control a bit to get that sweeping sound.

 

[Mutant]

Or something a bit better:
http://www.admiralquality.com/products/NaiveLPF/


And welcome !