xp will now be applied during combat
Fixed the description on Dragonhide and increased its cost a little bit.
Added a missing keyword to a few spells so that NPC's will comment on them being dangerous.

If you use Vaati88's Apocalypse patch (https://www.nexusmods.com/skyrimspecialedition/mods/26450), he forgot to include the script so the negative spell costs never gets applied. This file contains the script. You still need his patch as well.

This version does not apply xp during combat for your active spells in order to reduce script load