Turns out that CYDSTEPP is an okay find for the little bugger:
https://i.imgur.com/PoHXmN3.pnghttps://i.imgur.com/lnU6gN4.jpgPretty heavy on your resources, but strong on a map with few bosses nevertheless. CYDSTEPP leaves you no reason to kill anything before your first boss, and pretty much trivializes VT runs in any shorter dungeon. Namtar's Ward+Transmutation Seal make for an incredibly potent prep combination, giving you both an initial CP boost and money to fuel your shop regen ability. Speaking of regal perks: it also synergizes fantastically with CYDSTEPP. Get your mana pool up to 16 (assuming mystic balance), and this guy turns into a better warlord than anyone else could ever imagine to be.
That being said, I don't think this method is broken. Much like his kamikaze compatriot (may he rest in peace), this rat can't spike his way much further than through 2-3 bosses (be it with underlings or with shops) . It also faces a dilemma similar to how elves interact with refreshment: it can't both have the big CP cake and eat it. Not to mention how both poison and manaburn stop it cold. Sure, there's the ward/orb to remedy this, but scumming for either of those and an early CYDSTEPP at the same time is pushing it.
Definitely liking this version more than the previous one. Most vicious endeavors seem pretty doable, except for VGT - I really don't think that's going to happen the way the rat is now.