Shrivelling (the "Mystic Gun") is a staple level 0 card for almost any Mystic that wants to fight at all.

For those starting with the game, this is a good (but not exceptional) card. It allows Mystics to fight decently. Compared to the .45 Automatic...

• Equal or -1 skill value for each fight. Most mystics have 4 or 5 willpower. A Guardian usually has 4 combat, which means they beat out Mateo or Jim when you factor in the .45's +1, but go even with Akachi or Agnes. Note however that Mystics typically have an easier time boosting their key stat, with cards like Holy Rosary.
• One resource cheaper. Mystics are usually resource starved.
• You take 1 horror if you reveal a bad symbol. Mystics usually have high sanity pools, so this is not a huge issue, but it can add up if you get unlucky.
• Takes up an arcane slot, which is a competitive slot (equivalent to hand slots for Guardians).

Shrivelling comes off about even with the .45.

As time has gone on, we have received few other level 0 arcane assets that allow you to fight with willpower - Azure Flame is very similar, while Wither doesn't give you that coveted +1 damage. Shrivelling remains competitive as a result. Consider Azure Flame if you would prefer to take damage than horror. Or even run both!

How come no one is wondering about that rose? A person in a suit getting shrivelled to nothingness with a rose in their hands? Is it a Mafia threat thing getting an emphatic answer? Some weird burial? WHAT IS GOING ON? Well, at least the flower is not affected.