Level Zero (5e Variant Rule)
From D&D Wiki
Some DMs may want to begin a campaign with the players as commoners or other similarly weak individuals, either for narrative reasons or to further simplify gameplay to better teach the core mechanics. Players at 0th-level have the following features:
- You begin play with -100 XP
- Do not choose a class: you begin play with only your racial and background features.
- You have 1d6 Hit Dice. Your maximum hit points is equal to 6 + your Constitution modifier.
- Your proficiency bonus is +1
- You begin only with the equipment granted by your background, or 4d4 gp.
- When you reach 0 XP, you gain 1st level in a class. That class' Hit Dice replaces your existing 1d6 HD, and the classes "Hit Points at 1st Level" replaces your maximum hit points.
In most cases, you do not start with any weapon proficiencies (the exception is if you are an elf or a dwarf, or a human with the weapon master feat).
- XP Thresholds
A Dungeon Master creating a combat encounter for a party of 0th-level characters should use the following XP Thresholds (DMG p. 82)