- Fear checks: When adventurers confront threats they have no hope of overcoming or are exposed to something particularly horrible, the GM may call for a fear check (Wisdom save). A character who fails the save is Frightened or Stunned for 1 minute (GM’s choice). A new save might be required after that time if the situation is sufficiently bad.
- Horror involves more than simple fright: it entails revulsion and anguish. Often it arises when adventurers see something completely contrary to the common understanding of what can and should occur in the world, or upon the realization of a dreadful truth which they are helpless to refute. In such a situation, the GM may call for a Charisma saving throw to resist the horror. On a failed save, a character’s personality is overwhelmed and they develop some form of trauma response. A Modify Memory spell can erase the traumatic event from a subject’s mind, but the use of such powerful mind magic can lead to dire consequences.
Rest and recovery
- You may only spend hit dice at the end of a short rest if someone makes a Medicine check to bandage and treat your wounds. On a result of < 10, they expend two uses of their kit. On a result of 10-19, they expend one use. On a result of > 19, they expend one use and you regain one hit die. You may use this hit die immediately or save it for later. If the healer’s kit has fewer uses remaining than necessary, the effort is wasted and the kit is expended.
- You can spend hit dice at the end of a long rest without a healer’s kit, but you don’t automatically heal to full. You don’t regain hit dice at the end of a long rest.
- You may only spend up to half your hit dice at once (round up). The extra die from a Medicine roll of 20 or greater doesn’t count.
- You regain one hit die per 4 character levels after at least one day of non-strenuous activity (downtime), or one for every 2 levels under the care of someone with the Medicine proficiency. A single doctor can care for a number of patients equal to their Medicine proficiency bonus. This counts as strenuous activity.
- Medicine checks in especially unsanitary conditions are made at disadvantage. Those made in especially clean conditions are made at advantage.
Combat and Movement
- Flanking: If your target has hostile creatures flanking it (engaging it in melee combat from opposite positions), you have advantage on attack rolls vs. that target. Exception: Creatures which lack a visual sense or which can see/sense the area all around them simultaneously.
- Swimming in armor: Any armor which imposes disadvantage on Stealth checks also imposes disadvantage on Swim checks and imposes double movement penalties on Swim speed. The feat “Medium armor master” negates the skill check penalties with regards to scale mail and half-plate.
- Stealth: You have to break line of sight to Hide, either through Heavily Obscured areas due to darkness or atmospherics, or else actual physical blocking terrain, like a wall or object. You can’t just make a hide attempt without something blocking the enemy’s view. (Incidentally, this means a successful hide attempt can be made from some enemies but not others, depending on their position and what you’re using to obscure yourself.)
Success means you managed to get behind something and they don’t know where you went (just where they last saw you), while failure means that even if you did manage to get behind something, you were observed in the process and they will probably chase you to your hiding spot. (Credit: slightly edited comment by redkat85 on D&D subreddit)
- Dark magic corrupts those who dare use it, granting great power at the cost of their soul.
- Arcane spells cast by wild mages or in wild magic zones can have unpredictable effects.
- Translation magic is very limited; see Spell Changes for details.
- Scrolls do not exist. Any scrolls found in random loot will be replaced with spell formulas, which sell for the same price and can be used for scribing the appropriate spells into one’s spellbook (wizards, Tome pact warlocks) or for learning unusual spells without the need for research or experimentation (other casters).
- Bards are divine casters. Song of Rest works on long rests, not short.
See also Spell Changes