While a bit short, this game has a lot of character. Where the player’s in depth moveset sets up for a proper boss fight, all wrapped together by a nice little story.
First I want to talk about the art. While the visual style is a bit rough around the edges, it has a higher level of detail than we usually see in a jam. And since everything has consistent pixel density and quality, it gives the game a bit of a stylized look that works.
The title screen specifically makes a good first impression, giving the player something unique that showcases the tone of the game, but still fitting into the games overall artstyle.
In game the characters look great, containing lots of animations that make them feel alive. However, the background does feel a bit basic. While it’s important to not distract or obstruct a player's view in a game like this, the background makes up 90% of what the player sees, making it one of the most important sprites. I think some subtle animation with the clouds moving using a parallax effect could go a long way in bringing your scenes to life.
Along with that, a lot of screen space goes unused during actual gameplay. The top ~30% of the screen is unreachable and doesn’t contain anything visually interesting, making the game feel a bit off center. I would suggest raising the ground level up just a bit so that the player isn’t looking at the very button of their monitor at all times. And if you wanted to go the extra mile, you could make the camera more dynamic, zooming in/out to make sure the player and boss are on screen, without leaving quite as much extra room.
On a different note I think the font choice, while visually fitting, can be a bit difficult to read. Additionally, I noticed some special characters are not working (most obvious during tutorial), which is likely related to the web build of the game. For future projects, I suggest leaving a downloadable version of the game on the itch page in addition to the web build, since the web version never looks or runs as well as a local copy.
As for the audio, I think the music does a good job of setting the tone on the title screen and has a loop that is long enough to not feel overly repetitive. I’m not sure why there’s no music during the “Story” scenes when reading the scrolls, since I think it would have fit well there too.
However, I don’t think this music fits particularly well during the boss fight. The intensity of the song is quite low, and clashes with the action scene you create through the gameplay. A song with a higher tempo could give your boss fight a lot more energy.
Also as a small note, there's an awkwardly long pause before some of the music loops, which I suggest trimming down to avoid silence.
As for the sound effects, I think the boss sounds work well and convey the information they need to (even if they are a little goofy). However I would suggest adding more sound effects, specifically to player actions to give more feedback.
Simple actions like jumping, dashing, shooting, changing spells, etc. would feel better with a sound. But more importantly, hitting the boss and getting hit should have sounds as the player feedback would help make the game easier. As is, it's not always easy to tell if I got hit by an attack, so a sound effect to clarify would help a lot. And sounds when landing hits would make me need to look where I’m shooting less, allowing the player to focus on dodging.
Next I want to talk about the gameplay. Having a tutorial is super important, and the one you implemented is a very nice touch. However, making it a second button on the title screen makes it easy to miss, which will likely cause some player confusion (I’ve made this same mistake during previous jams). It doesn’t need to be a hard requirement, but something like a second menu after the player hits play, asking if they want to do the tutorial, ensures they won't miss it. Although, making it required is often safer, since players will skip optional tutorials and then complain that your game is confusing.
Another note about the tutorial is that I think it throws too much at the player all at once, but still doesn’t contain all the game's mechanics. It wasn’t until I looked at the Itch page before my third playthrough I realized there was a double jump and dash. To fix this, I would suggest breaking up the tutorial into multiple screens, where leaving one takes you to the next. Then you could have a platforming room to just teach movement, and another for combat. Overall lowering the amount of text on screen at a given time, and giving the player more time to process each feature.
As for the controls, I think the movement was standard and easy to understand, however I found the scroll wheel selection for the spells a bit clunky. Having to look away from my player to the top left to see what spell I cycled to made changing spells mid fight feel risky. Because of this, I would have preferred using number keys to let me switch to the exact spell I wanted without looking away from the action.
Along with that, it would be nice to know each spell's cooldown without switching to it. As is, the player needs to keep looking at the top left repeatedly to see if the spell they switched to is the one they want, and if it's on cooldown, which becomes very distracting when trying to use all the spells optimally.
Jumping over to the movement, I think the general feel was ok but had a few oversights. The left/right movement felt a bit stiff, with either very little or no smoothing at all. And while you don’t want a game like this to have “slippery” controls, having a very small amount of accelleration/deceleration makes things feel better.
Along with that, it would be very nice to have a variable jump height, where releasing space lets you not jump as high (accomplished in most games by increasing gravity when the player releases space and still has a positive velocity). It’s pretty standard in most platformers today, and makes games feel less floaty.
As for combat, I think the boss attacks are all well designed and fit well together. However a slightly longer delay between attacks would have helped (At least after the horn attack with the slow projectiles), since it was common for him to start a new attack before all projectiles had cleared the screen. This often leads to “Unfair” feeling moments where the player has to avoid 2 attacks at once.
Also, since the hitboxes are not super clearly defined through the art, I would suggest always leaning in favor of the player, and making boss/attack hitboxes smaller, since players will never get upset about a close dodge not hurting them. However you don’t just want to make enemies hitboxes smaller, since then you have the problem of the player missing shots when they think it should hit. To address this in the past, I’ve given enemies 2 hitboxes. A larger one for the player to shoot the enemy, and a smaller one for the enemy to hit the player (Although I understand this is probably overkill for a jam).
My last comment about the combat has to do with the spells. While there is a large variety, I think the 3 long range spells accomplish the same thing (Dealing more damage from a distance) and are more or less interchangeable with each other. This leads to the player usually wanting to spam every spell off cooldown without any thought.
This unfortunately isn’t helped by the 4th close range spell, since the distance is so short (and the boss hitbox is so unclear) that it’s almost never safe to use. Resulting in the player most likely avoiding this spell.
To address this, I think replacing some of the current spells with more situational spells that have other utility than “Dealing damage” would have helped. For example, things like a spell that deletes all projectiles on screen for when you're in trouble, a short range spell that also heals you to make it worth the risk, a spell that freezes the boss and pauses their current attack for when the player needs a moment, etc.
Overall, while I think there are areas for improvement with the movement and spellcasting, this is still a very fun and polished game. Boss rushes are a notoriously time consuming genre to pull off, so it’s impressive to see a well made boss fight in a jam. I apologize if this review was a bit much, but I'm doing this to all the games from this jam as I think critiques help us grow.