The game is well-made (I personally had no problems with the grapple controls), but I'm not sure what the point of the echolocation is. You can just spam the button every couple seconds to see everything. I'd suggest looking more into the game design concepts of push & pull - what risk should there be to using your echolocation too often?
Also, while I really like your use of colors (making the players glowing green & the enemies bright red), it was a little hard to determine what anything was supposed to be. Were the foreground enemies just moving boxes?