Reuse weapons:
Split off a trooper with no grenades or bazooka rounds after the rest of the unit has been killed. The new unit will have the weapons from the dead troopers.

View map:
Press Pound, 0, or Asterisk while playing the game.

Switch units:
Press 1, 2, or 3 while playing the game.

Extra options:
Press Option at the "Boot Hill" screen to access sound volume, button configuration, and screen resolution options.