The subways are mostly done now in the playtest, and I also did a lot of quality of life improvements so I decided to update the demo too! While I don't plan to add more content to the demo, I did add a river of water that will spawn in a new save (and shows off the new water mechanic). Changelog that affects the Demo:

• Added water and an underground river
• Added buckets
• Added footstep sounds
• Added a clear option to the painter to remove paint
• You can now climb ladders from any direction (even if the ladder is behind you)
• Adjusted the shield so it no longer works with 0 power
• Other adjustments and minor improvements

What can you do in Aground Zero?

• Mine ores, gems, and other resources
  
• Build structures
  
• Rescue survivors
  
• Fight enemies and bosses
  
• Explore the ruins of Earth
  
• Upgrade your tools and Protosuit
  
• Craft items and automate factories
  
• Balance power generation and usage
  
• Meet some familiar faces in 3D
  
• Reach the surface, and beyond?

• OS: Any 64-bit
• Processor: 2.0 Ghz Dual CoreMemory: 3 GB RAM
• Memory: 3 GB RAM
• Graphics: OpenGL 3.0+
• Storage: 1 GB available space