The Payload

If the cart reaches a point, you advance to the next song, it's basically a indicator when the song is ending.

( I know the hud is innacurate to how many points there is on pl_badwater but it's a concept. )

The HUD

Basically you can get hurt but not in the way like you do in FNF.

The Health Cross displays how many hp you have, if you reach zero, you die.

The Ammo Counter well, it displays how many bullets you have, the ammo depends on what class you chose. ( In this case, BF is a Scout, but if this were a mod, you could change the classes of BF and GF, more on this in the next part. )

Damage

The ways you can get hurt are Bullets, Projectiles, and Afterburn.

You can dodge attacks using A and D, just like you do in the game, you can also change this to use the arrows instead but as default it uses A and D, but you cannot dodge fire.

Note this is part one, next part's coming soon. ( Hopefully )