This is the Attributes package.
It includes not only Attributes and an AttributeManager, it also contains a custom Editor and PropertyDrawer.
These package lets you easily add Attributes to any object.
Enemies need Health, Damage.
Players need Health, Damage, Speed or maybe even max items in Inventory.
This AttributeSystem uses points for abstraction.
Each attribute has a minimum and maximum amount of points.
You can increase or decrease points.
The value of the attribute is then calculated based on current points.
Everything can be edited in a custom editor.
Example scene and scripts included.
[Included] Essentials
[NotReleasedYet] Conditions
[NotReleasedYet] HealthAndDamage
[NotReleasedYet] Input
[NotReleasedYet] Pathfinding
[NotReleasedYet] GameObjectPool
[NotReleasedYet] Spawner