I really like the concept and the effort put into it. It had a Half-Life feel and that was super good.
However there were several things that just made me want to quit playing. The overall style was not good - the starting screen was seizure inducing and the whole game was pretty much different shades of red. Normally this isn't a problem but it is when everything is so saturated red, everything was vying for my attention and it was giving me a headache. The text was also hard to read with all that saturated red just everywhere. That being said the shield effect was cool - the way it affected the stuff around it was nice.
The gameplay was good but tedious. For example double jumping and shooting was awesome, but moving was meh. The true tedious part was farming the energy to double jump and farming the energy to actually shoot the weapon. The grappling hook never worked for me - it always just shot me off the platform.
The overall game ran smoothly and I had no problems getting started. However, I noticed the E button for me didn't work on the very first level so I ended up skipping the tutorial section.
The level design could also use some work - the controls are decent but I don't know if heavy platforming should be a thing for this type of game, especially when you seem to respawn at the beginning of the level.
I would be very interested to know how the game turns out, so please finish it!
-Azulles