Many great ideas here. Directing shots by being the target is a really fun idea, and creates an interesting dynamic with how to kill the enemies indeed. The visuals, sounds, UI and UX were all very well polished for such a short jam - even for a team of 6. I played it several times. Feels like you're shooting for a top 100 spot, and I think it's deserved - I gave it a max rating.

Switching gears to be way more nitpicky:

1. The control tutorial could've been better. The first time I played I didn't manage to pay attention to all the controls. Ideally, you shouldn't assume the player knows the controls before they've passed a very basic test where that control is needed. But it's a only minor complaint, since I got it after 2 or 3 tries.
2. The title screen was slightly off, aesthetically. I get that it's retro/neon/Tron computer style graphics but it still gave me a way lower first impression than the actual game did. Even the settings looked smoother.
3. The audio feedback for losing health is good, but it'd been nice with a slightly more apparent visual feedback as well. I know there's a screen-shake but late game there were many other screen-shakes, so perhaps some color along the edges or something
4. The XP bar blended in a little too much with the hearts indicator to me - I didn't notice the hearts as well as I wish I did. Perhaps also because the game generally has lots of "thematic graphics" like the background grid of similar width, which has no functional utility and confused me ever so slightly. In a bullet hell / arena shooter with decreasing breathing room, it doesn't seem very useful to me to have so many uniformly colored elements display the information I need. Perhaps you could've altered the looks/color of the player for the 3 different heart "states" or something.
5. For the first while I didn't realize that you could go on the top side of the tank too - perhaps you could've started zoomed out to the entire arena and then do a quick zoom animation into the normal camera.
6. I didn't like the chromatic aberration effect on the enemies. It's a bit distracting for an action-packed game, in my opinion.
7. My hitbox was not incredibly intuitive , especially for the player's odd shape - but fortunately it wasn't too big to feel very unfair.
8. Minor bug: The music stopped after a while and didn't come back. WebGL version, Chrome, and having it in an unfocused tab for a few minutes.
9. Very minor thing - in the settings, there were tick marks but you could also set the volume to half between the tick marks, which seemed a bit odd (but the granularity is much appreciated)

I'm also curious if there's more to the slightly odd name EB-87 than the meme, and what I presume is 1987. And also the Michelangelo head as a player?

Here's a few screenshots from my playthrough: https://imgur.com/a/dyS9Z0C

Very well executed concept, simple but fits theme and become interesting when you add more power ups. Great visuals, i really like this vaporwave glitch effect. Great entry!

I like the Vaporwave style, but I think it would worked better if the music was, you know, like in vaporwave.

The game gets pretty challenging quickly too with new ennemies, bonus points for that.

I love this games concept. The graphics are really nice too! (my only complain is the games performance, which gets worse after some time)

The game concept and graphics are really cool! I enjoyed it and had more fun the further I was in the game!

Sadly I am not very good at this kind of games so I will have to practice a little more haha

The music/sound design was also very nice and put together! All in all it felt like a very polished game with a great idea that could be worked on further!

Really one of the coolest games I have seen in this jam with this type of mechanic! 

Congratulations and great job!

Really enjoy all thouse funny enemy sprites as well as the overall balance of difficulty, the concept of upgrading your own difficulty is also well presented.