Hey sorry about that. I think I have an idea on how I can help.
Have you tried mashing the space bar or did you only press it once? Everytime you press the space bar when the target is focused on a gremlin, you drain their HP by 1. The gremlins have about 30 HP (90 for the dark green one), which would take you about 30 space presses to defeat one. I've should've been more precise on the instructions when I said that.
if that didn't work, I'm sorry in advance, but I thank you for your feedback and I'm glad you like the concept!
- Orangebox Games