Sidekicks
Source: Tasha’s Cauldron of Everything p. 142
This section provides a straightforward way to add a special NPC-called a sidekick-to the group of adventurers. These rules take a creature with a low challenge rating and give it levels in one of three simple classes: Expert, Spellcaster, or Warrior.
A sidekick can be incorporated into a group at the party’s inception, or a sidekick might join them during the campaign. For example, the characters might meet a villager, an animal, or another creature, forge a friendship, and invite the creature to join them on their adventures.
You can also use these rules to customize a monster for your own use as DM.
Creating a Sidekick
A sidekick can be any type of creature with a stat block in the “Monster Manual” or another D&D book, but the challenge rating in its stat block must be ½ or lower. You take that stat block and add to it, as explained in the “Gaining a Sidekick Class” section.
To join the adventurers, the sidekick must be the friend of at least one of them. This friendship might be connected to a character’s backstory or to events that have transpired in play. For example, a sidekick could be a childhood friend or pet, or it might be a creature the adventurers saved. As DM, you determine whether there is sufficient trust established for the creature to join the group.
You decide who plays the sidekick. Here are some options:
- A player plays the sidekick as their second character-ideal when you have only one or two players.
- A player plays the sidekick as their only character-ideal for a player who wants a character who’s simpler than a typical player character.
- The players jointly play the sidekick.
- You play the sidekick.
There’s no limit on the number of sidekicks in a group, but having more than one per player character can noticeably slow down the game. And when estimating the difficulty of an upcoming encounter, count each sidekick as a character.
Gaining a Sidekick Class
When you create a sidekick, you choose the class it will have for the rest of its career: Expert, Spellcaster, or Warrior. If a sidekick class contains a choice, you may make the choice or let the players make it.
Starting Level
The starting level of a sidekick is the same as the average level of the group. For example, if a 1st-level group starts out with a sidekick, that sidekick is also 1st level, but if a 10th-level group invites a sidekick to join them, that sidekick starts at 10th level.
Leveling Up a Sidekick
Whenever a group’s average level goes up, the sidekick gains a level. It doesn’t matter how much of the group’s recent adventures the sidekick experienced; the sidekick levels up because of a combination of the adventures it shared with the group and its own training.
Hit Points
Whenever the sidekick gains a level, it gains one Hit Die, and its hit point maximum increases. To determine the amount of the increase, roll the Hit Die (the type of die appears in the sidekick’s stat block), and add its Constitution modifier. It gains a minimum of 1 hit point per level.
If the sidekick drops to 0 hit points and isn’t killed outright, it falls unconscious and subsequently makes death saving throws, just like a player character.
Proficiency Bonus
The sidekick’s proficiency bonus is determined by its level in its class, as shown in the class’s table.
Whenever the sidekick’s proficiency bonus increases by 1, add 1 to the to-hit modifier of all the attacks in its stat block, and increase the DCs in its stat block by 1.
Ability Score Increases
Whenever the sidekick gains the Ability Score Improvement feature, adjust anything in its stat block that relies on an ability modifier that you increase. For example, if the sidekick has an attack that uses its Strength modifier, increase the attack’s modifiers to hit and damage if the Strength modifier increases.
If it’s unclear whether a melee attack in the stat block uses Strength or Dexterity, the attack can use either.