How much to train casting with fighters

[Grimm]

Is there any point at all for an armored tank (Fi, Be, Mo, any spellless fighting class) to train spells? I've trained it with MDFi's but I've never gotten to a point where I had a spell I could use in a real situation. Does anyone have success with it?

[KoboldLord]

Depends on your armor, and the books you've found.

Assuming you don't find War Chants or something fantastic very early, you're probably going to strap on some chain mail or plate mail early on. With that on, it's basically hopeless so you're going to have to put spellcasting off anyway. You'll pick up that critical first level whether you want it or not, and then leave it.

Around Vaults or so, or Swamp if you're lucky, you'll find your first good dragon hide. Dragon, ice dragon, and swamp dragon are the ones you're looking for. These armors are just as good as the common branded heavy armors, but they're light enough that grinding spellcasting high enough to cast in them is actually viable. You'll want to find a robe, a leather armor, and then your target dragon armor to practice with. Rings of wizardry and a staff of energy will be handy, but not strictly necessary.

Once you're ready, take your dragon armor into vaults and kill something BIG. Stone giant or something. Then run away to a cleared level. Once you're on the cleared level, switch to your robes, remove your shield, and victory dance your low-level utility spell. You're looking for stuff like Blink or Repel Missiles, not Magic Dart or other things that depend a lot on spell power. Once you've emptied your xp pool, switch back to your dragon armor and look for another stone giant (or whatever) to kill.

Once you're casting at excellent in robes, switch to leather and continue victory dancing that same utility spell. Once you're at excellent in that, switch up to your dragon armor. Once you're at excellent in that dragon armor, start taking off rings of wizardry until you're at excellent even without any wizardry items. Then start victory dancing until you cast at excellent even with your shield.

Expect this to be a long and tedious process, but it will be more useful than yet another level of your main weapon skill. Victory dancing up a second school will be quicker than dancing up the first, because you'll already have some spellcasting skill.

[Grimm]

Very helpful answer. I'll give this a go in my next game.

[szanth]

Even if you -don't- have teleport control, blink is very useful. It's like an "Oh crap" button that works faster than the teleport scroll. It at least generally gets you far enough out of the way so that you can pop a scroll and be slightly safer while that works its magic.

[Stormfox]

I've done it in 0.4.5. MDPa that had IMB at Excellent while wearing storm dragon armour and a dwarven shield, and no wizardry items. Only took about 20k turns from the time I learned it to the time I was able to cast it reliably.