R15Character

function on_spawn(player: Player)
    if local character = player.Character then
        local root = character.HumanoidRootPart
        local humanoid = character.Humanoid
    end
end

The character a player spawns on the R15 rig: a Model with HumanoidRootPart as a Part?, each of the fifteen body parts as a MeshPart?, Humanoid with its Animator and HumanoidDescription, BodyColors, and the Animate and Health scripts. Every part is optional: a part can be gone by the time the code reads it.

Player.Character and Players.LocalPlayer.Character type as R15Character? when [roblox] rig in alloy.toml is R15, the default. The editor's alloy-luau.rig setting wins over the file. R6Character is the other rig.