Based on player feedback I've made the following changes:
- Added particles that telegraph to the player visually where enemies are spawning from
- Added particles when a drone is charging the player
- Added sfx for the player's blaster shooting
- Added sfx for explosions because explosions

Additionally:
- Imrpoved audio balancing
- Implemented the BGM as heard in the player
- Improved visibility of the drones' shield color
- Laser tracers are now rendered even when behind the player
- The maximum number of drones that can be in the level starts at 3, and ramps up to 9
- The spotlight indicating the player's health has been change to emphasize the different brightness levels
- Fixed a bug where the drone's charging sound wouldn't play