Your link mechanics were very interesting. Bouncing the nodes around back and forth and manipulating them through the play space felt fair. The mechanic takes mastering but once you get the hang of it, you can really do a lot of damage and enjoy moving them around~ feels good. I played with the game controller, so thanks for including those controls.
The powerups may need some tuning in my opinion. That speed powerup makes you way too fast, like to where you lose control. Its a great jump in the feel of the controls from their original values. It recreates the learning curve all over again.
For the powerup that increased tether length, is the trade off that enemies will deal more damage to you (the player) in exchange for increased range, or do you deal more damage with your tether while getting to extend its range? This wasn't too clear but I did die pretty quick after I chose this.
There are some bugs going on and I think I pinpointed exactly what occurred. Somehow while I was tethered to the yellow box during the boss fight in Wave 2, I happened to somehow kill and damage the boss but my tether did not even touch the boss so I was confused how this happened. I just know I was attached to the yellow box when it happened, maybe while dealing damage or getting dealt damage by and or to the boss while being tethered to the yellow box. I was surprised because the Boss still had nearly a full health bar and then suddenly I was alerted I cleared the level and was prompted to chose my 3rd upgrade (which was the increased tether range).
However when I started the third level, my node characters were reset to their scene start positions but the tether link broke and both ends of the tether remained in their ending positions spot from where their two points had been positioned in the previous wave at the moment the boss was destroyed, when the tether was anchored by the yellow extension box. Both tether ends extending out from the yellow box stuck in the game space where my two nodes were when the scene ended / the wave cleared. I lost my tether connection the tether end points were locked in those same positions from the previous scene. And now I could only manipulate the two nodes with no tether in between them.
I could not get a screen shot because I died to fast in the 3rd scene when it started, which is why I wondered if the damage I had taken from enemies, had been increased due to the power up. Or maybe even selecting the powerup, that would change the distance for how the tethers would behave had an influence on recalculating their positions after the scene load / wave change, that caused the end points of the tethers to get stuck when they were both coming out from the yellow box instead of their original connection between the controllable nodes.
The enemy projectiles were a hassle, but if you play the game enough and develop patience and mastering of placement and control over your nodes, you can adapt. I feel there is quite a balancing act that you as the player need to develop in order for you to destroy the enemies while dodging the bullets, and while not taking damage. There is a difficulty spike in this way that is very sudden. You don't have time to adapt to the ramp in difficulty unless you play numerous runs. This could also just be my skill issues... lol!!
Could use some higher music volume. It sounded very feint, and the sound effects were overpowered. I think the feedback between the object interactions was fair. I feel that if you varied the sound effects and alternated the pitches of the explosions and collisions, or even had different explosion sound effects that cycled, it would go a far way to emphasize a dynamic feeling of the object interactions.
Either way... I enjoyed the mechanics you presented. It's a very engaging concept!! The little faces on the objects are really cute :3