It sort of reads that you must have the Autohypnosis skill to attempt this rather than either that or Concentration.
Maybe change it to
Normally, a toon will always fall if it deliberately jumps instead of merely slipping or falling. However, a toon may use the Autohypnosis or Concentration skill to convince itself it's walking on something solid, the toon must succeed at a DC 20 skill check every round.
Mortis
That looks go as well.However, a toon may use the Autohypnosis or Concentration skill to convince itself it's walking on something solid, this requires a successful DC 20 skill check every round.
That looks go as well.
Regrads
Mortis
Cleon said:My preference would be making him effectively unkillable - regeneration plus rejuvenation plus immunity to "Save or Dies".
I wouldn't mind what you suggested above:
Umm, let's say yes to the sphere. Hard to imagine avoiding that. What about a bag of devouring? Hmmph.
Rejuvenation often has some condition that ends it; we could just mention under rejuvenation that there are rumors of substances that can destroy toons.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.