I'm glad to see this thread, as I've been mulling over my own reservations about Ori and the Blind Forest since I cleared it to 100% two months ago—and admittedly, I hesitated to post an exacting dissection of it like I do for some other games because I do find it a little weird to do that when I know the designer is hanging out with us in the room and reading everything.
Speaking of which, if you're on the Switch port, I highly recommend perusing the behind-the-scenes featurettes in the gallery after you're finished, even if you had a mixed opinion of the game like I did. You can really see the love that was put into this game pouring out of every crevice, and I can appreciate how it took some risks with original systems that not every Metroidvania developer necessarily has the resources or ambition to implement. It's in the nature of taking risks and breaking with conventions that not everything will go over well, particularly if players come in expecting a specific genre (from the marketing, imprecise word-of-mouth, or whatever else) and come in with a preset frame of mind. When I see people here gripe about "combat", I think there is some of this going on—a certain reluctance to play ball with Ori on its own terms and understand how the radius-based homing attack fits into the overall toolkit.
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This won't be the aforementioned dissection. But I stand by my first impressions from October:
The short version: it's clearly the most beautiful game I've ever encountered in the Metroid genre, but this often comes at the cost of visual clarity, and half the time it's trying to be a Limbo-like "cinematic platformer" stuffed to the gills with QTE-like instant kills, which doesn't click at all with the genre's exploration/progression model—a format that works best when it revolves around stamina, consistency, and long stretches of surviving chip damage from one rest stop to another (which Hollow Knight understands so marvellously). Here it's trying to be two very different kinds of games at once, and I'm not sure it works. I think Ori is still an essential experience, but people expecting a Metroid-alike should know what they are getting into. Most of its reputed "difficulty" actually just comes off to me as bad design—pockets of trial-and-error OHKO platforming where the challenge comes from the legibility of the hazards, not from cleanly executing the moves. It's a testament to the magnificence of the rest of the game that I still found it highly worthwhile to grit my teeth through the irritating parts and see everything else it has to offer.
In short, I disliked all of the escape sequences (the set pieces that stand in as end-of-dungeon boss encounters) and thought they deflated the experience every time. In a way it helped that they were so beautifully crafted: the execution was so polished that it left me utterly convinced that the idea of mashing this specific kind of speedy do-or-die platforming with an exploration game built around not-entirely-linear power progression just doesn't work as a concept. In other words: if I didn't like it in Ori, I'll probably never like it from anybody. (MercurySteam took a crack at something similar with the Diggernaut escape sequence in Samus Returns, and it might be the clunkiest thing about the otherwise excellent Samus Returns.)
That's not a knock against all escape sequences broadly, as of course they've been a long-running staple of the genre whether you prefer to save or kill the animals. But Ori's "platforming bosses"—along with some of its progression gating on the world map—have a pretty serious problem with excessively depending on instant kills (or "effective instant kills", as I call them, when you fall somewhere with no chance to recover using your current toolkit and you can't do anything but take damage until you die). The escapes are clearly made to look and feel spectacular when you do pull them off fluidly from start to finish, and they do, but the actual process of determining your path often feels like reverse-engineering the designer's intent rather than expressively using the move set to improvise, react, and make desperate recoveries from sloppy fumbles.
I've heard some people describe this as difficult platforming, and it's really not. Executing the right moves is rarely ever the problem; the demands on your precision are not all that stringent (though the delay in waiting for the arrow to swivel to the intended angle threw me off repeatedly when using the grapple). In my case, anyway, the cause of death was almost always legibility: not having enough time to read what's going on or locate the "intended" path (or in certain sequences where you get sniped for standing in the wrong place, understanding where the safe zones are), and dying repeatedly until I can perceive what's going on. And this is in a game where the legibility is a bit of an acquired taste from the start; it takes a bit of experimentation to consistently parse what is or isn't safe to touch, or what the hitboxes are.
There's a place for this sort of difficulty design—even the incredible DKCTF dabbles in it with some of its mine cart or Rambi stages where there's nowhere to go but forward and fast—but I think there are times, in the platforming genre and elsewhere, when tight margins of error just reduce player freedom without adding much excitement or interest. Generally, I find that chases, auto-scrolls, stealth sequences, and other such "cinematic" set pieces work best when they have a certain elasticity to their level of tension, if you know what I mean: a sense of being ahead or behind—banking up room for error, or losing room for error, with a chance to make unplanned recoveries from mistakes.
Which brings me to my next point: that with respect to Ori specifically, the instant-kill design clashes like crazy with the entire progression model of a Metroid-alike where the incentive to explore is to build up your life and energy reserves. The whole point of poking around the map, apart from compulsively defogging the map for its own sake, is to build up a safety net for yourself. In Metroid—and I'm not saying that games of this sort should slavishly imitate Metroid—this, in turn, is what makes low-percentage runs an interesting speed category, and creates a whole spectrum of risk/reward from low-% to 100% for technical exploration on the part of the player. So when the big boss-like set pieces discard this, yes, they're evenly balanced platforming sequences that play out the same way no matter how much or how little exploration you've done (and you do need to accommodate players who just zip directly from one marked objective to the next)—but they also trivialize everything else you've done in the game. As a result, they feel a bit detached and impersonal, and the separate impulses of the "Metroid plus platforming challenges" synthesis don't seem well integrated.
Likewise, some of the progression gating on the map has a similar problem: it often errs on the side of killing you (or not permitting you to escape death) instead of chipping at your health or signalling that the route is blocked some other way, and while Ori is hardly alone in doing this—you can't dive into the acid in Hollow Knight until, well, you can—when you combine this with some of the legibility issues, it isn't that friendly to experimentation.
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To be fair, despite the proliferation of Metroid-inspired designs this decade, there really aren't a lot of games that do what Ori does: and I don't just mean the stunning artwork but the extent to which the game embraces its 2.5D-ness (2.5-dimensionality?), if you get my meaning. It's a game that radically pulls away from thinking in grids, tiles, or geometrically regular surfaces, and which has a very "live" physics system. (If you look at it this way, Yoku's Island Express is arguably one of Ori's closest cousins.) That comes at the cost of a certain degree of precision when it comes to, say, parsing which slopes are open to wall jumps and climbing, or landing accurately on the edge of a narrow plank dangling off a vine. And a lot of that is an acquired taste if you're an experienced Metroidvania player and have certain expectations for how things work or how to read your visual field; you
do need to learn how to read this game specifically and grasp how your movement options fit in.
Despite my reservations with Ori and the Blind Forest, I think there is quite a bit of potential in the foundations it laid, and I actually think it doesn't get nearly enough credit for the things it tried that are original and unique to the overlarge category of games that people call Metroidvanias (a term I don't much like anyway, and which I've always found especially misleading to people coming in from Metroid rather than Castlevania). People talk up the artwork and ambience above all else—and deservedly so—but not nearly enough about the physics or environmental fluidity as a distinct branch of design, one worth exploring much further. I remember thinking something similar a few years ago about SteamWorld Dig, which certain players were pushing as a Metroidvania when it was really nothing of the sort: that this might not be that substantial a platforming/exploration experience
now, but the foundations were definitely there to make that happen. Then Dig 2 came along and knocked my socks off.
This is a roundabout way of saying I really do wish I could take up that hypothetical offer to drop by Moon Studios and playtest Will of the Wisps.