The world in Infinite Worlds I.S.T. seems more like Kirby-2 than Krypton-1 to me, but yeah, as the "weirder" of the two, the Kirby line should probably have the higher mana level. In both worlds, more free-form mages, like Necron -- those who, built under the first edition of GURPS Supers, would've had "Magic Power" -- could use the Magical Powers Talent from p.159 of GURPS Fantasy.
(Speaking of Necron, I've thought for a while that the vignette for the "Magic" chapter should involve him muttering to the effect that he could've started the Mage Age a decade early if those fools at the University had only listened to him...)
(Speaking of Necron, I've thought for a while that the vignette for the "Magic" chapter should involve him muttering to the effect that he could've started the Mage Age a decade early if those fools at the University had only listened to him...)