I’m actually starting up a group with a 0-level adventure to help them get into the character and “know” each other before play. They’re all kids in a town that’s attacked (I’m using the Flight from Fallston module).
Their attributes are the standard array, they have their full racial benefits and background benefits (not counting the feature), +1 Proficiency bonus, and all of the proficiencies and skills granted by their classes. Their age begins as the base Adulthood for their race (meaning they’re all young, but neither children nor adults).
Sorcerers and wizards get 4+Con mod HP. Artificers, bards, clerics, druids, monks, mystics, rogues, and warlocks get 5+Con mod HP. Fighters, paladins, and rangers gets 6+Con mod HP. Barbarians gains 7+ Con mod HP.
- Artificers begin with the Magic Item Analysis feature.
- Barbarians begin with Rage (1/long rest, +1 damage) and Unarmored Defense (half Con mod added to AC).
- Bards begin with Inspiration (d4) and Spellcasting (1 cantrip, 2 spells, 1 1st-level slot).
- Clerics begin with Spellcasting (1 cantrip, 1 1st-level slot).
- Druids begin with Spellcasting (1 cantrip, 1 1st-level slot).
- Fighters begin with Fighting Style.
- Monks begin with Martial Arts (1d4 damage) and Unarmored Defense (half Wis mod added to AC).
- Mystics begin with Psionics (1 talent, 1 discipline, 2 psi points, 1 psi limit).
- Paladins begin with Divine Sense.
- Rangers begin with Favored Enemy (+1 damage).
- Rogues begin with Expertise (1 skill) and Sneak Attack (1d4 damage).
- Sorcerers begin with Spellcasting (2 cantrips, 1 spell, 1 1st-level slot).
- Warlocks begin with Pact Magic (1 cantrip, 1 spell, 1 1st-level slot).
- Wizards begin with Spellcasting (1 cantrip, 3 spells, 1 1st-level slot) and Arcane Recovery.
If their character starts with a Martial Weapon, give them a Simple weapon. If they start with a Simple weapon, give them an improvised weapon. If they start with Medium armor, give them Padded Armor. If they start with Heavy Armor, give them Hide Armor. Finally, find whatever their starting wealth is by class and give that many items from their starting packs (if their wealth is 5d4×10, then give them 5 items).
They start with -150 XP. When they level up, they add 1 point to each Attribute, they add 1 Hit Die (rolled and added to their current HP), add the rest of their features, lose their current items, and gain their starting packs. Finally, they “agree” to meet in one year at the tavern they ended up in (a tavern in Neverwinter where they’ll go on to meet Gundrin Rockseeker for the Lost Mine of Phandelver module).