wow, i have no idea how you managed to come up with and design a game with item synergies given the game jam duration, but this was great! love this take on the item-management based genre, backpack hero management gameplay contextualized with a more real time action top down experience is pretty fun! besides some balancing adjustments (3 sweatbands for the win xd), i feel that they all work really nicely with each other and provide good scaling for future waves! there were also a nice variety of enemies that synergized well with each other, making the combat feel tense and engaging! though i think the ai is a bit abusable since you can just take advantage of corners, since the bullets are big enough to usually collide with the corner if they stop at the right place (also your bullets being smaller than the enemies makes it easier for you to abuse this since it'll less likely for your bullets to collide with the corner). the random room generation is also very nice, but sometimes you can get really unlucky with the enemy spawning and run into scenarios where you can't really avoid getting hit. these are small nitpicks though and easily adjustable, the game is still really fun!
the abberated items locking their position creates a neat element of strategy in terms of how you want to try forming your inventory to future-proof yourself and not place yourself in potential bad positions later on down the line, which i think works pretty nicely in a game jam setting like this where people will only on average be playing for a few games, but at a broader scale i can see players constantly resetting and getting frustrated if the aberration rng doesn't go their way (especially since shop items are highly randomized). this next part is just me playing armchair game designer so you can skip it if you'd like (your game idea already works xd). to avoid this problem, i think instead of aberrations locking an item's position (which is a huge negative to the player) you can instead make items either weaker or have an inverse effect when aberrated (and can be sold for less than the original sell price). i think this allows for an interesting dynamic where player's are encouraged to frequently change their builds, constantly move around their items, and plan for future build pivots if they don't want to be affected by nerfed items (and it also allows players to experiment with the different items in the game more, thus engaging more with the game). though through slight nerfs, players can still opt to continue with their build that contains weaker items if the synergies are strong enough, allowing for players to make these kind of tough decisions during play. though again, the aberrations locking their positions is also a fun mechanic to engage with, this was just me doing a thought experiment xd!
the presentation also is really nice, again nice level generation with cool different themes to switch up the visuals! the spiral effect on the backgrounds of the shop and main menu look also really nice, adds some visual interest in the background through the spiral motion while not being too distracting! also love the attention to detail with the shop items where they tilt when you hover over them, feels very nice! every sprite asset just looks nice in general and feels consistent with the art-style that the game is aiming for! the BGM is also really nice to listen to, adds to the vibe of the game really nicely, well done!
overall, really fun game! whats here is already super addicting, and i could see this getting expanded even further to something really cool! great work!