Long and Short Rest Mechanics

Long rests will be rare: In this campaign setting and in particular in the campaign called Sigils Sealed characters should expect many hours of play to pass between long rests. In general you should expect 4 to 6 combats or significant events between long rests. So conserve your spell slots and other long-rest-recovered abilities! Cantrips or weapon attacks will be crucial to conserve spell slots!
Short rests will be relatively common: In contrast to long rests, characters should expect a short rest to be relatively common. Players should expect the possibility of a short rest after approximately 50% of significant combats or events.
Long Rest Mechanics: As stated in the PHB, a character can use a long rest to regenerate, at most, half of their total hit dice (rounded up). In addition, a long rest along with proper ingestion of food and drink during that long rest, recovers only one level of exhaustion. Lastly, long rests in this campaign will often carry an additional burden that players will learn early in their campaign.
Short Rest Mechanics: As stated in the PHB, a character can use one or more of their hit dice to recover hitpoints during a short rest. Note that only HALF of your maximum hit dice are recovered during a long rest, so use your hit dice wisely during your multitude of short rests between long rests.