A
I thought bilinear transformationMobius Stairs?
Arcadians were quite good (esp. for a mode 5 game) - another Orlando great (eg Zalaga, Firetrack), but Planetoid was really the yardstick (Neil Raine games (still) rule!).LOL, had Chucky on my BBC Micro. Arcadians though kept me out of mischief for longer.