Combat consists of a web of several mechanics:
Health is the amount of time a living being has left on their lifespan. It can also be interpreted as points. A being normally will not age within the Super Store, meaning that their Health stat can only stay static or increase.
When a being is damaged by attacks, they will gain an injury related to the attack that will immediately take away a certain amount of points, and then drain more points from Bleeding damage.
One can increase their Health stat by training.
Attacks are a mechanic that almost any living being can utilize. There are several different kinds of attacks, such as Immediate, Bleeding, Poison, Diseased, etc..
Immediate attacks are attacks that deal immediate damage, Bleeding attacks drain Health points and must be staunched, Diseased attacks deal damage over long periods of time, etc..
Attacking is a mechanic that almost any living being can utilize. It is not the same as attacks. Attacking is the act of starting an encounter with an opposing being. If one were to start attacking another being, it may retaliate or run away, or some other consequence might ensue, such as a damaged relationship scale with an NPC.
Boss Fights are a mechanic that activate when the player character triggers them. Example: the player character angers a powerful NPC enough that they trigger a boss fight, the player character enters an area containing a boss, etc..