In my low-fantasy world, monster drops are created when a magical creature is slain; its lifeforce is released and interacts with ambient magic to either recreate body parts or alter objects in or around the monster. This explains why weapons become enchanted upon killing a monster, as well as why drops are a thing.
However, how magic works is that if a creature has a spiritual connection to an element, magical energy of that element will connect to it; sort of like how an empty space sealed inside an object sucks in air once the seal is broken. The connected magic inside the body mingles and fuses with the creature's life force (its spirit) and by extension its body.
Why does this matter? When a monster is killed, its magic is connected to its spirit, which is not of this world. Magic, however is of this world, and thus the two separate, albeit imperfectly. What's left of the creature's spirit is anchored by magic to the body, but the body was destroyed by the powerful release of magic upon its death! Therefore, this magical Remnant attaches to the nearest magical living thing; the person who killed its former host.
The monster's wild magic latches on to the 'tame' magic of the monster slayer, and as their magic grows and evolves (magic grows with you, you see) the magic of the monster is organized and takes on another form, eventually becoming a companion.
TL;DR: Anyone who kills a monster, or multiple monsters, will eventually gain a Companion; a magical creature born of the lingering essence (Remnant) that attaches to whoever slew it. However, any serious adventurer or monster slayer will then be able to gain an army of little friends, and I really want to avoid this; what's the fun in reading about someone sitting back while their animal 'companions' take care of their enemies for them? Therefore, my question is How Can I Limit Monster Slayers to a Reasonable Number of Companions So They Can't Form Animal Armies?
In more specific terms, How Can I Limit Monster Slayers From Gaining Too Many Animal Companions When They're Obtained By Slaying Monsters?
- Monster slayer and adventurer mean the same thing for the purposes of this question, since adventurers are known for slaying monsters.
- By animal companion, I mean the standard RPG variety; a creature that accompanies someone and obeys their commands. These can be ordinary (like a wolf), somewhat fantastical (like a hornet the size of a poodle), or flat-out extraordinary (a giant red dragon).
- As already stated, Companions are created between the interactions between a slayer's magic (this magic is manifested as an RPG-style Class) and a monster's Remnant (AKA lingering magical essence) as the slayer gains Levels. Levels are an expression of one's personal growth, gained by experience and monster slaying (since slaying monsters enhances one's magic). In other words, it takes time (and Levels) to gain a Companion after slaying a monster.
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