Ophidian Update: New Map and Optimizations

- New map with 10 new enemies and 3 new bosses unlocked by completing first map on Hard Difficulty
- Optimized performance regarding damaging enemies
- Added a particle trail following the player while moving
- Added a shadow outline to damage text to increase its visibility
- Slightly nerfed Minigun's Fire Rate
- Buffed Guided Missile upgrades: Explosion Chain, Phosphorus Missiles