This is going to be quite different from my normal posts, but please, hear me out on this.
You should play DELTARUNE Yellow. It's good. It's a little jank, a little rough around the edges, but if you're willing to accept that, I think it's good.
Currently, the game is two chapters, with an intended total of 5.
Maybe you know me enough to just take my word for it, but, if you don't, I have a lot to say that might help convince you this is worth your time. Please. Hear me out.
CONTEXT:
Deltarune Yellow is a fangame of a fangame. Its premise is simple: It's DELTARUNE, but for Undertale Yellow, taking place in what is presumably the Deltarune universe but focusing on the UTY cast and characters instead.
I want to be very clear about something. I, personally, am a bit of a UTY critic. It's not an actively bad fangame, but, personally, I didn't really get much out of it. I felt personally that its story was fairly surface level, and I didn't feel like the game did any of the sorts of things that I felt an "Undertale prequel based on the Justice Yellow-SOULed human" should have done. It, to me, felt like it barely even focused on Justice as a theme, and it barely challenges anything you go into it assuming. There's way more I could say on this, but I want to make it clear that I'm making this post as someone who really didn't get much out of UTY and thinks it's just kind of Okay.
Deltarune Yellow, in my eyes, straight up does everything that I think Undertale Yellow should have been doing. I think it attempts several things that I've been saying for years UTY should have been done, and I think it better executes a few ideas that UTY itself attempted, but didn't commit to enough for my tastes.
Maybe it's not the deepest thing of all time, but I think it's genuinely trying to Do Things, and this alone puts it way above most other fangames and fanworks I've seen.
I'm going to try, now, to go into some specifics. I feel like most of this is stuff that is maybe better experienced in the game itself, so if you feel like what I've said is enough of a sell, I suggest you just go play the game now.
PART 1: THE GAMEPLAY
The thing that I think I noticed first with Deltaruen Yellow is that the gameplay itself is good.
I'm not going to talk about the Overworld here too much- but please know that this fangame straight up has the best Overworld mechanics and gameplay of any fangame I've played, bar none. There's certain things that this fangame does that I've never even seen attempted. If you like the Mario and Luigi series, this game is a must-try.
But, what I'm actually going to talk about is the battle gameplay.
One of the biggest things I felt like Undertale Yellow was lacking in is that it doesn't really change up the formula very much. You can basically play Undertale Yellow the same way you'd play Undertale. To put it another way: Clover is basically just the same as Frisk. There's no unique mechanics added on top of the existing system, and no incentive to work within the existing system differently, so it kinda just feels like More Undertale. This isn't the worst thing in the world, but I was kind of hoping to see something a little different.
To put it simply: Deltarune Yellow's party feels different from the Deltarune party, and the way you actually strategize throughout this game in any given battle feels very different as well.
I could probably write an entire essay on why the Deltarune Yellow party is interesting and well designed, but I'm going to restrain myself to be as vague as possible here.
I think the single biggest adjustment this game makes is that Cole (Clover) has access to a new ACT that's in very single battle, in addition to Check- "Non-Lethal Shot". This ACT shoots a rubber bullet at the enemy and costs 25% TP, dealing less damage than a regular attack but having a "False-Swipe" effect, always leaving the target with at least 1 HP, unable to land the finishing blow.
This might not SOUND like it changes much... but in combination with two other factors, this completely changes the way you approach combat in this game.
There is no "Pacify" in Deltarune Yellow. It's Undertale logic- when enemies are low on HP, they become Sparable, not "Tired". This means that any party member can take advantage of a weakened foe.
The enemies in DELTARUNE are all pretty easy to Spare, usually only requiring one or two ACTs to get into mercy range. This is not the case in Deltarune Yellow. The enemies are much more "Undertale" pilled, often requiring multiple ACTs in a specific order in order to successfully get them down. The mercy meter still exists, but often you'll find that certain ACTs are only effective if you've already laid the groundwork with other ones.
Your S/R Action equivalent is almost always a borrowed ACT from the main ACT menu (I'll explain this more in a moment).
To attempt to give an example: There's this gear-based enemy in Chapter 2. One of the ACTs is to "Spin" the gear. But this is actually not very effective until you use the OilUp ACT on it to make it spin faster.
Your other party members' S/R Action equivalent isn't a standard "Add Mercy" ACT, either- their Action is to use that "Spin" ACT, the very same one that Cole has by default in his ACT menu.
What this means, then, is that sparing this enemy is not as simple as just throwing all your ACTs at it- If you do not spend the time to use the OilUp ACT on this gear, it's going to be trickier to spare them.
But what that means is that... there's an actual REASON to choose to FIGHT enemies to whittle them down now. Because, effectively, the ability to attack your enemies acts as a more reliable, if trickier, alternative mercy condition. You can, for instance, choose to dedicate Cole's turn to slowly ACTing on enemy A, while attacking enemy B with your other party members, which you normally wouldn't be able to do because Enemy B requires attention from Cole as well.
And the Non-Lethal shot ability is the key to making this feel reliable- One of the biggest issues I always have in Deltarune with attempting to use Pacify strats is that if you attack the enemy too much, you might accidentally hit them too hard and make them LOST. But because of Non-Lethal Shot, you don't have to thread the needle, since you can always reliably chip them down into spare range.
There's way more I could say about the battle system, but I think I'll save it for another time. To put it simply: I think that due to the way that skills are spread across the party, and the order of the party in turn order, this game actively feels different on a turn-to-turn basis.
PART 2: THE STORY (NO SPOILERS)
This is kind of tricky to talk about without getting into specifics but I'm going to try to do my best to explain how I feel:
The narrative of Deltarune Yellow is perhaps not the deepest thing of all time, but, in my eyes, there is something to be said about it, and I personally am much more invested in this story than I ever was in the story of the original Undertale Yellow.
Additionally, whlie it doesn't fully commit to this (yet), there are moments in this game where I legitimately felt like I had to question whether I was going to do what I felt I was "supposed" to or whether I should do something else instead. It's not the craziest thing in the world, and I'm hoping the game does even more with this in the future, but I was at least thinking this way to some extent, and this, to me, is something that I think UTY should've been entirely centered on.
PART 3: ADDITIONAL THOUGHTS
Pretty quickly in the game, you obtain the Magic Lasso, which grants an additional universal ACT on top of Check and Non-Lethal Shot; Apprehend. It costs 40% TP, and requires you to succeed a timing minigame in order to Capture the enemy with the Lasso, teleporting them to the Dark Jail. You are intended to use this against the dedicated "Criminals"- every chapter, you're given a handful of wanted posters of criminals you need to find in the Dark World, who must be Apprehended as an optional sidequest. However, you can also choose to use this ACT on... anyone..! And what this means is that there's effectively a third way to end battles:
Either you FIGHT them, you SPARE them (If possible)... or you Apprehend them.
I've always been an advocate that UTY should have added an additional method of ending battles that's an in-between state- Winning a battle through violence, but not actually killing your enemy, only injuring them. I think that this effectively fills that exact niche.
Seperately, the armor and gear in this game is really good. Like, really good. If you've read my other posts, you know how I am- I really like the gear system in Deltarune, and while I think this game is slightly lacking in some respects (I think there should be more gear that directly boosts your base stats), it absolutely carries with some of the insane gear options. Basically every piece of armor you find in this game once you're in Chapter 2 has SOME sort of additional benefit to it, and these benefits are often way more interesting than anything you'd find in Deltarune.
As an example: There's an armor I found that makes you start every battle with 35% TP and raises the TP gained from DEFENDing with the wearer from 16% to 21%. That's like, insane. That's so cool.
The Chapter 1 Secret Boss armor is also especially cool for a certain reason... but I really don't want to spoil what that reason is. If you know, you know.
Thirdly, I really enjoy how the party feels more versatile yet weaker than the main Deltarune party. You have access to more total spells (In fact, you slowly gain more spells over the course of the game in a handful of different ways, it's crazy!!), but at the same time, it kind of feels like you're not as efficient as the Fun Gang is. You lack Pacify, and while you have damage options, it doesn't feel like you have anything quite as powerful as a good-old Rude Buster. I think this is a really interesting balance. In Undertale Yellow, it's made explicit that Clover is simply not as powerful as Frisk is. I never liked this detail, because it kind of felt like it made all of our hardships in the game feel less impactful- even the toughest things Clover has to face are probably not stronger than, like, Undyne is in Undertale, lorewise. This is also seemingly true of the Deltarune Yellow characters in relation to the Fun Gang... but here, it kind of feels way more intentional and it actually "matters". Your HP is much lower than the Fun Gang's is and scales much slower (the game is obviously balanced around this, but it's a neat detail), and while you have access to similar spells, they're "weaker" in isolation. The party feels way more "squishy" than the DELTARUNE party, and I think it's really well done. Simultaneously, there are way more options for you to choose from, making strategy more interesting, while also maintaining that these characters are simply Not the heroes of prophecy and are going to struggle a bit more to get through the dark worlds. It's good. It's really hard to explain this without going into detail but I really enjoyed the party balance and design.
CONCLUSION
I think this is about all I can say on this fangame without getting into specifics. I hope I've made it clear that this is a fangame I deeply enjoyed and I highly, highly recommend that you play it.
It is a little rough around the edges. It's a little jank. The art is sometimes not the prettiest, and while there's a few original tracks, it doesn't have a complete OST and re-uses a lot of basegame tracks. But I do not care, and neither should you, because those aren't the things that actually matter in the end. If you're willing to play a game that's a little bit rough sometimes, I think you will enjoy Deltarune Yellow- even if you are someone who actually does not like the original Undertale Yellow.
I could probably make a second post going into more detail on the stuff I didn't go over here... but that's for another time.