In order to play as Heat a in the second game, you need to make the correct choices through both games. If you do choose to play as Heat in DDS2, the character of Roland will be replaced! It would be a good idea to make two saves if you want the option of both characters.

In your DDS1 game, in Coordinate 136 when Heat challenges you, answer "No, I can't..."

In Ajna after defeating Ravana answer "It doesn't matter."

Beat your DDS1 game and after the credits, save the cleared game. When you start a new game in DDS2, load the DDS1 clear data from your card.

In your DDS 2 game, after defeating Yaksa Abaddon answer, "We're Comrades".

After defeating the Real and Fake Varna, walk down the corridor to where Heat is waiting and answer, "I do..."