Don't go off on one on about how Eva sucks. Don't go off on one about how Eva sucks. Don't go off on one about how Eva sucks!
Ahem. The Mecha Hack Mission Manual, as revealed in its assorted previews, gives us a Hybrid class. A half machine, half kaiju monster, a Hybrid works likes a normal mecha until you run the generator down, where upon it goes apeshit. This is a nod to the hugely popular Neon Genesis Evangelion, or simply Eva, a franchise I haven't liked for about, ooooh, twenty years? I'm gonna keep it brief, but the reason for my distaste is twofold. The first, the personal one, is that I battle with mental health issues, so I do not get along with the tone anymore. The second is how toxic an influence it was on the Mecha genre, as it (re)popularised the idea of such shows being absolutely miserable experiences. I'm into this stuff to have fun, not to feed my assorted issues. There's my bias, up front. So, you have the basis for running an Evangelion, or Evangelion-adjacent, campaign now. Assuming you wanted to, how would you? Here's some answers.
The Challenge
The key thing is tone. Eva is not that interested in creating an internally consistent setting that maps easily to game mechanics, Unit-1's stated height is given as between 40 and 200 metres for example. It's more about mounting horror and mental breakdown. The anime is effectively an Ultraman homage for the fashionably grim, and, SPOILER ALERT FOR EPISODE 2 OF A MASSIVELY POPULAR TV SHOW, has no actual mecha in the regular cast. The Evangelion units are mutilated Kaiju on extension cords, and fights are increasingly desperate as the so-called Angels are immune to most attacks. This includes most of the mecha-scaled weapons demonstrated in the show, so there's an element of puzzle-solving, at until the crushing despair becomes ever-present. And then there's the religious aspect, which people make a bigger thing of than is merited. You could lean into that, but it's set dressing, in much the same way scifi usually co-opts old religions like the Greek pantheon. Meanwhile, The Mecha Hack is meant to be simple, quick and fun. So then, the heavy lifting is probably gonna be done in the role playing side. And there's nowt wrong with that. But if you wanted to make the Hybrid more mechanically like an Evangelion, you could replace the Mawbeam ability with the following.
External Power: While attached to an external power source, you gain Advantage on Reactor rolls. If you are not, instead roll your Reactor Die at the end of each Moment.
This neatly demonstrates the feast or famine nature of your average Eva, as opposed to just counting down. You could build further by mapping out Tokyo-3 with power points and how long the cables reach, and so on. The point here is to increase tension without adding paperwork. If players want to run off batteries, they can, but it has to be a risk. Also note that I am assuming that AT fields are either subsumed into HP, AP, or Gamesmaster Fiat. Yes, you could make it a rules mechanic of its own, but it's not interesting enough.
Sanity, and other afflictions
It can reasonably be argued that much of Evangelions runtime, and especially the "End of" film, sees young Shinji Ikari going insane while inside the belly of Unit-1. This is what happens when your director is clinically depressed and also lost track of the budget, poor guy. The film remakes are reputedly less traumatic to watch, but I've no inclination to check. This prompts a question of "should this be a rules mechanic?". Well, good news, the Cthulhu fanbase beat me to it! And the answer was "yes". More specifically, The Cthulhu Hack offers easily adapted and minimalist rules for existential terror and dribbling lunacy. Which work much like the Reactor Die mechanic, which I was quite impressed with. Granted, piloting a giant robot requires a rethink as to what violent acts would be a strain on sanity, but I leave working that out as an exercise for the reader.
Wrapping Things Up
Yeah, I don't especially like Eva, but that doesn't mean you can't like it. Nor do I dismiss it as RPG fodder, which is why this article exists. Some ideas you just have to write down, ya know? And, if you try this?
Well, lemme know how it turns out.