Finally, I’m ready to share my mods for my 2015 villain sets which we all know are lacking in design when compare to the Toa.
I tried to keep the silhouette of the sets the same because I like their general ides, just not their final looks.
Winter Wave:
- Lord of Skull Spider
So I’ve changed his legs to CCBS attached to Glatorian necks, which I swapped with those trans-neon-orange technic beams. I also replaced knobbed gears with black ones to better suited his color scheme.
To make the body shape more spider-like, I shortened his abdomen by using shorter beams found in hunter Umarak’s legs, and rounded the end with Terak’s hand piece.This way the function still works the same, just with shorten grip.
With these mods, LOSS finally fits right in with the rest CCBS-heavy sets. And he can really hold that non-canon GMoSS now. 
Summer Wave:
These sets generally suffer from unproportionally short legs (except Skull Scorpio of course), so that’s what I’d fix in every one of them.
- Skull Grinder
I simply use body construction from SSvsMM & Skull Scorpio “Kulta Kal” combiner to beef him up and differentiate him from other skull villains. And to deal with his gearbox friction, I added a ball & socket type friction like Onua Master.
- Skull Basher
Not much change here. I just swapped his leg bones with Onua Uniter’s longer trans-purple ones.
- Skull Scorpio
This most jarring thing about this set is the clunky function. So I restructured its technic function to be more compact and streamlined. This design is based on Leewan’s mod I saw on Eurobricks forum.
However, since I didn’t have all the parts he used, I changed some aspect of the design so it’s not an exact copy of the original anyway.
This iteration of the function can even hold its pose in either fully closed or opened positions.
Here’s the LDD file for the function, in case anyone want to look more into it: LINK
- Skull Slicer
I didn’t like how all six of his limbs were essentially the same built, so I moved the parts around to distribute the color more evenly.
I also accented his legs by giving him long bones from Umarak Hunter’s arms and shells to make his legs stand out from his arms.
- Skull Warrior
I found nothing wrong with him in particular, so I’ve left him untouched.
I also added extra spikes here and there, but that’s entirely up to your preferences. 