Recently the game gets updated with new skins but these skins cannot directly be added in the level editor, only by Trigger Actions, file editing, or copy pasting from a file edited map.
Some of these Skins also have incorrect blood colors or other mistakes that I will also note below.
The skins are:
151 - 155: Variations of the same skin with different colors, name unknown (Blood is dark purple, unknown if intended to be regular blood color #7f0000 or not)
156: Shadow Noir Lime (Has same Blood as CS-Ghost, probs intentional)
157 - 161: Alternate variants of 151-155
163: Light Battlesuit Oryx
164 - 165: Blue and Red Variants of Heavy Marine
166 - Orakin
167 - Husk (Uses Heavy Psi Blades by Mistake)
168 - Hex (Uses Heavy Psi Blades by Mistake)
169 - Arrin (Uses Heavy Psi Blades by Mistake)
170 - Heavy Usurpation Soldier (Mistakenly doesn't have reduced movement speed)
171 - Cyber Grub S1lk (Mistakenly has Human Blood rather than #e6bf33 Cyber Grub Blood)
172 - Grosk
173 - Futuristic Knight
174 - Uncivil Proxy (Not selectable as DM skin)
175 - Nexxon Contractor
176 - Assimilated Reakhohsha Operative (Actually seemingly an Usurpation Destroyer, doesn't use Reakhohsha sounds or blood color #df81e0)
177 - Slayer
178 - NEXXON CAPTAIN (Name in all caps in game mistake, not mine)
179 - Savage Falkok
180 - Savage Phoneix* (Failed spelling of the word Phoenix is actually in game, not my mistake, also blood color might be slightly off from #284ff0 used by regular falkoks)
There's also the following skins that I believe to be Event Skins.
38 - Yellow Noir Lime Variant
39 - Magenta Noir Lime Variant
162: Pinkine (Purple & Black Marine Variant)