Info gathered from the Atari Manual:

GAME VARIATIONS

1-1: Starts with Dragon 1 (Green) | Single Player 1-2: Starts with Dragon 1 (Green) | Two Players

2-1: Starts with Dragon 3 (Blue) | Single Player 2-2: Starts with Dragon 3 (Blue) | Two Players

3-1: Starts with Dragon 5 (Red) | Single Player 3-2: Starts with Dragon 5 (Red) | Two Players

4-1: Starts with Dragon 7 (Orange) | Single Player 4-2: Starts with Dragon 7 (Orange) | Two Players