The "Use Magic" rules seem to be set up for an unusual proliferation of magic - ie, anybody can do it reasonably casually with a small number of hoops during the course of an everyday adventure, even if spookies and monsters are better at it - it might go wrong but there's a reasonable chance of success.

I'd have expected it to be a fairly big deal in any event, and for (say) the average Mundane or Professional to cast even a "non-big magic" spell to be astounding and epic. Do you interpret the requirements more stringently than I'm reading them (eg, just discovering a spell is a really big deal all on its own), or do your games tend to be high magic environments?

Having thought about it, maybe I'll just not worry about it :-)

Here's my monster, any opinions?

Mind-Eater (Kai’Jedlek)
Type: Devourer/Breeder

Out of Host
Description: A fat squishy blob about 6 inches long, with sharp claws and teeth
Powers:
•   Devours brain to control host (see Custom Moves below)
•   Scuttles short distances quickly
•   Leap up to 15ft in any direction (including into the air)
•   Can remain dormant indefinitely.
Attacks:    Bite/Scratch: 0-harm hand
Armour:   2-Armour from being a difficult target to hit
Harm Capacity:  4-Harm
Weakness: Attempting to devour a host with extreme levels of caffeine in the bloodstream will temporarily stun the monster – it falls off and remains still for about a minute. Armour is temporarily reduced to zero.
Custom Moves:
•   Devour Brain: Latches onto the back of the neck and burrows into the host’s brain through a small puncture wound, effectively killing them and taking control of the body.

In Host
Description: To a casual observer, the host will appear unchanged. More careful observation will reveal a small wound at the back of the neck, slightly clumsy movements and possibly slurred speech
Powers:
•   Remain in host for around 24 hours (between 12-36 hours depending on body’s condition)
•   Full physical control of host (with reduced fine motor control)
•   Access to memories of host
•   Exceptional physical strength
•   Ignores pain
•   Reproduce single offspring in current host’s abdomen approximately every 3 days

Attacks   :
•   Punch: 2-harm hand
•   Improvised weapon: 3-harm hand
Armour: 1-Armour from being insensitive to pain
Harm Capacity: 8-Harm
Weakness: If the host dies in the first hour, the Mind-Eater has not matured enough to escape and will also die
Custom Moves:
•   Escape Host: Bursts out of the back of the neck and reverts to “out of host” stage. (must have been embedded in host for at least 1 hour)


(note: edited slightly, I missed a few things)

Thanks! Yes, if the hunters are interested enough to find out they may eventually discover that "the magic" appears to have come and gone throughout history. What's causing it, how the cycles work, and whether they can influence or stop it are things we'll (hopefully) play to find out.

Thanks, a good idea! I'd thought of maybe replacing the library with a private database accessible by smartphone - it's a little more 21st century in any case!