can't locate the source

The graphics are definitely old-school. I found it really difficult to aim, however - since you can only rotate in the eight cardinal directions, it makes it very difficult to hit enemies, especially when they're somewhat small. The mechanic for picking up enemy shot types was a little hard for the same reason, but it was a good idea.
The inclusion of multiplayer is great. I didn't get to test it since nobody's around in the wee hours of the morning, but the it's pretty neat that you included it at all.
Also, don't forget to include your source code!

Yeah, I don't get it. So you get the power of an enemy that you manage to kill? Saying that somewhere would be good. Nice aesthetic, but hard to play.

The focus of the game primarily is multiplayer, I should have added in the notepad what each of the enemy spells give, their charge and damage, I'm sorry for missing that out.

As for the aiming, I can fix that, but I'm not sure if it'll be allowed through because it'd be after the deadline. It'd be rigged to the cardinal directions, so only 8 directions as opposed to the "swing" you can get from this, but that means more stable aiming.

I'll be sure to address these issues and more if I make an updated and improved version/sequel to this.

The retro style works well here and feels really authentic.

Like others said, controls were a little squirrelly. Overall, decent game. Fit the theme appropriately, etc. Definitely 5/5 for graphics and audio. The monochrome sprites, dithering, chip tunes and sfx, etc., are truly a thing of retro beauty. Nice work!

I can't shoot when going to the top-left or bottom-left directions on my keyboard. (The w+a or a+s keys prevent j from being recognised.)

The game felt a bit sluggish also (maybe because of Wine), and not being able to shoot several bullets at the same time felt so space-invadery... I had to read the comments to know that I could get dead enemies' powers, because I hadn't managed to kill a single one before. (Afterwards I managed to kill one or two.)

Interesting graphics :). I first thought the background meant something but apparently no (the hero could run at different speeds when walking on different tiles, also the bricks should stop the player/monsters.)

Also there is no progression indicator, no health? No goal... When I died the game printed the same time each time (165 seconds.) I wonder what that means.

81 seconds!

I have NO idea what is happening with this game but I enjoyed the apple 2e / archon style graphics. I basically mashed the fire key and once in awhile some kinda mini-enemy stuck to me and did stuff. Would probably be a lot more fun if I could decipher what the heck I was supposed to do or what health level the other enemies were at.