GameMaker Gang!! Really fun entry, focusing on gameplay definitely paid off! The randomized challenges greatly increased replay-ability and kept me on my toes. Having to complete 5 challenges with 5 lives fit well with the pentagon theme, and resetting the players lives after a successful challenge was much appreciated. I ended up rage quitting after 5 or so attempts after I kept losing to the 3 or less health and special enemy challenges, but I had a lot of fun in my runs.
The art style is simple but an effective use of the allowed shapes and your little bits of visual polish take it to the next level. The pentagon animation after beating a challenge is a great example of this. The music and sfx are crunchy and fit the arcade feel superbly, 5/5 on audio for me. The gameplay fits the theme very well and the being confined to the limited space of the pentagon in different ways for each challenge made for some engaging gameplay.
One critique I have is that it was often too difficult to see enemy's yellow bullets (especially when on the light green or orange challenges) and this made for some frustrating deaths that felt outside of my control. I'm not sure how to go about fixing this but some more visual contrast between the enemy bullets and the rest of the environment would have been greatly appreciated. Overall, there is an impressive amount of visual juice and overall polish on top of a very solid gameplay loop that comes together in a very fun package, great entry!!
edit: also the tutorial is very well-executed, gets all the necessary info to the player in a very concise manner and then lets them get right into the action, kudos