For quality TGA.
So you have nice Alpha Channels.

PNG is not propperly supported by Gamestudio.
It would be the better format though.
(smaller, more options)

Some small recent games of mine:
Griefer 4k http://damocles11.byethost9.com/griefer4k.html
Kobold 4k http://damocles11.byethost9.com/kobold.html
Cave 4k http://damocles11.byethost9.com/cave4k.html