Doom System

At the start of each combat encounter, the GM gains a special resource called Doom based on the CR of the encounter, as detailed in the Doom by Encounter Tier tabic. The GM can usc Doom to influence the results of creature die rolls, turning the tide on the PCs or helping a creature last just one turn longer. The GM can spend Doom in the following ways:

• Give a creature advantage on an attack roll.
• Give a PC disadvantage on a save.
• Once per encounter, refresh, recharge, or otherwise gain one additional use of a limited-use feature, such as a dragon's Breath Weapon, a legendary creature's Legendary Resistance, or a spell in a mage's Spellcasting.

Doom is optional and exists to give creatures some extra staying power against particularly powerful, crafty, or resourceful PCs. Keep in mind, Doom doesn't have to be used in every combat encounter. As a GM, consider using Doom in an encounter if:

• The combat encounter is likely the only combat encounter the PCs will face that day, and the PCs are well-rested.
• You have multiple experienced players.
• You have more than four players.
• Your players' characters have extra magic items, resources, optimized statistics, or similar aspects that make them tougher than average PCs.
• If the encounter is particularly significant to the story, such as the fight against the leader of an antagonistic organization working against the PCs, the final fight of a major story arc, or a climactic fight against a powerful antagonist.

DOOM BY ENCOUNTER TIER

ENCOUNTER CR	DOOM
0-4	1
5-8	2
9-12	3
13-16	4
17-20	5