Planar Shifts
Planar shifts cause strange effects on the unprepared, the sudden lurch through time and/or space often leaving their minds reeling. Confused and shocked, some minds seek the solace of sleep and dreams in an attempt to recover.
Planar Connection. A creature on its home plane has advantage on attempts to resist this challenge.
Sleepless. Creatures that do not require sleep are immune to the effects of a critical failure and automatically succeed at this challenge.
Reading the Shifts. A successful Arcana check allows a character to read the patterns in the planar disturbances and predict when they are coming, giving advantage to all members of the party against this exploration challenge.
The party must make a group Wisdom saving throw to withstand the mental shock of being shifted so jarringly across planes.
Critical Failure. The whole party is caught in the wake of a planar shift and moved 1d4 hours in time (backwards if the result is even, forwards if it is odd). In addition, all members of the party are cursed with planar slumber.
Failure. All adventurers that failed are cursed with planar slumber.
Success. Despite a slight feeling of unease, the planar shift causes no untoward effects.
Critical Success. Something unexpected appears alongside the party. Roll on the Boons and Discoveries table.