This species, which i have endearingly dubbed "the leech" until I can discover it's species name, makes up the next boss, Leech Lord, who currently has me pretty much stumped on how to advance. The part forward of the main body is it's mouth, and has a stun attack that can debilitate weapons and parts for a few seconds, effectively rending you neutral. the parts connected immediately right and left of the main body are it's connectors (obviously) which have a regeneration function, which the two times i had them were a godsend, allowing me to rest up and heal before trying to gain nutrients, allowing me to use nutrients exclusively for buying parts. the parts farthest left and right are it's movers, which only move in the directions their "hands" point. And finally it's combat parts, the forward pointing spiked tongues projecting forward from the connecters. These hellish french ticklers latch onto enemies (I.E. you) and slowly damage their target while staying firmly locked onto their target, and possibly (i'm not 100% sure on this though) healing the leech. The boss version of these guys is completely unlike the other two, he's fixed in place, but spawns minions who won't attack him or each other, instead working together to pin you and grind you into sad mush. i fought against hime 8 times in a row before i had to step away from my computer and do something relaxing before i returned to attempt subsequent (and as yet unsuccessful) attacks on this hellish nightmare. When asked, the devs stated that the game is set to a hard mode, and that this boss is an experiment. I imagine somebody has beat this abomination, and in fact it's why i've started this thread, in hopes somebody will come along and help me and all of us continue forward in an expedient way.
I know the way to beat the "leech lord", if you are talking about the one that surrounds and traps you. you want to take out its minions with snipers and slowly cut off its arms. The more you cut off the arms the less minions it can summon until it cant summon minions any more. Then just go straight for the head with snipers to remove the leeches and slowly dig into the boss untill his head is vulnerable, then just rush the core. Hope you find this helpful!