Allow for players wearing space suits or diving suits to use hoses to transport breathing gas to the player. Whatever gas/liquid is in the hose will be effectively the "atmosphere" the player breathes. The "breathing" action of the player can be implemented similar to a weak pump sucking the gas through the hose, so if a breathable gas is not constantly supplied the player will suffocate. This can be implemented in a number of ways.

1.) When a player is holding a hose and wearing a diving/space suit, they can right/left mouse button to connect the hose to their suit.

2.) New umbilical versions of the diving and space suits could also be created, and the suit inventory block has an included winch, meaning the umbilical is always connected to the hose.

In addition, a "bubbling" visual effect (the exhaled gas leaving the player's suit every few seconds) would be nice to include.