Spell Proposal: Heart of Ice

[Kersallus]

The Idea came to me as a reflective spell enhancer charm for ice magic, similar to the Ring of Flames.
Level 7
1-Charms
2-Ice Magic

This spell makes the caster becomes a nexus of pure ice, slowing the actions of all units on screen based on distance. This spell attunes the caster to the forces of Frost, increasing their Ice magic and giving them protection from cold. however, it makes them much more susceptible to Fire.

Units on screen have their actions slowed by 1-3 auts (static, based on spellpower and proximity, 1-2,1-3,2-3, etc) the caster gets a spell power modifier to ice spells like a ring of ice, along with cold resistance and fie vulnerability.

Thoughts?

[and into]

Because Crawl lets you train whatever elemental schools of magic you want, the *fewer* the parallels and similarities amongst them, the better.

Aside from that, I'm honestly having a hard time imagining when I would want to cast this. It would very rarely retain the same speed difference between you and the enemies you care about in LOS, and would nearly always increase the speed difference *against* your favor. That alone is not worth the gain of a single ice enhancer effect, in really all situations I can think up.

In addition to this you get a pip of resistance at the expense of a vulnerability, which is a bad trade off already, even if it weren't the case that the resistance you gain is a bit worse than the one you lose. Ring of Flames gives rC-- and rF++ but—and this is critical—you get flame clouds spawning adjacent to you, which is not only fun, but helps block a lot of cold-based attacks.

[Wahaha]

This spell takes 7 mp and 1 turn to cast. The benefit must outweigh the casting of another spell like bolt of cold or ozocubu's refrigeration. I think that there are few situations where it's really worth it. If hypothetically this spell took 0 aut and less mp to cast, it would be useful, because being slowed by 0 to 0.3 aut is often worth a spell power enhancer. It's particularly good for ozocubu's refrigeration because of rC. However comparatively ring of flames is a stronger spell, even if we're still thinking about the hypothetical instant cast and lower mp cost. This spell is also less interesting than RoF because it basically trades a small slow for spellpower and rC, while RoF has the clouds.

[Kersallus]

Say it didnt slow the caster.
What do you think then?
(Edited to reflect comment)

[Hurkyl]

I imagine the slowing effect should relate to the level of cold resistance a creature has (which means the caster doesn't need to be special cased, although probably still should be).

[and into]

There's already a strong ice spell that slows monsters, though: Metabolic englaciation. And there is already a way for ice magic to make it harder for enemies to kill you, but gives fire vulnerability (ice form, especially so when combined with oz's armor and/or condensation shield). I feel like a lot of the design space for the proposed spell is already covered, and in a way that does not parallel other elemental schools of magic so closely.