Descent: The Well of Darkness

At the start of the overlord's turn, before doing anything else, the overlord moves each boulder by rolling one red and one yellow die and moving the boulder the summed range along its arrow; any figure in a space a boulder moves onto is instantly killed (ignoring wounds, armor, and Undying), except figures safe in pits that the boulder merely rolls across; boulders remove rubble, are destroyed by walls or closed doors, and a boulder that collides with another is destroyed (p.5).

Breath attacks billow around obstacles (so they can curve around corridors and pass through rubble) but are blocked by walls and closed doors; a target is affected only if a small flying figure could trace a legal movement path from the breath's start square to the target while staying inside the breath template (p.7).

Bleed: when an attack causes bleeding, place bleed tokens and at the start of that figure's next turn roll the white die once per bleed token, suffering wounds equal to the total (ignoring armor) and then discard all bleed tokens; Daze: when an attack causes daze, place daze tokens and at the start of that figure's turns roll a power die per daze to remove tokens on surges, and each time the figure attacks it loses one yellow/green/black die for each daze token remaining (pp.5–6).

Before the game the overlord may spend event/trap/monster treachery to swap base cards for treachery-cost cards (paying the proper treachery type for each); any leftover treachery converts into extra starting overlord cards at a rate of 1 extra card per 2 points of leftover treachery (any type), up to a maximum of 8 starting cards total (p.4).

Place the bolt template flat against one side of the attacker (two squares wide at the base); Bolt affects all figures under the template and ignores rolled range (only missing on a miss), it flows around obstacles like Breath but cannot pass through staircases, walls, or closed doors, and if multiple figures dodge only one re-roll may be made (p.6).

When attacking with Swarm, you gain +1 power die for every other friendly figure adjacent to the target (up to the normal maximum of 5 power dice), and you count all friendly figures adjacent to the target even if those other figures do not themselves have the Swarm ability (p.6).