Life Force is the sequel to Gradius, so you might assume that our old friend the Konami Code would also work with this game.
And you'd be right.
Normally, you start the game with three ships.
But, if you go to the title screen.
Put in the famous button sequence
Up, Up, Down, Down, Left, Right, Left, Right, B, A
And then begin your game, you'll have increased your fleet tenfold
And if you have two players, hit Select before Starting your game to give both of you the battalion of ships.
And good luck! You'll need it!