 Koichi Ishii, the creator of the "Mana" series, decided even before he worked on 2002's "Final Fantasy XI" about creating new "Mana" games, but first wanted to create a goal for the new series, and eventually decided to make it about exploring how to add "the feeling of touch" to a game.After he saw the game "Half-Life 2" at E3 in 2003, he felt that its physics engine was the one he needed.