Patch Notes: Destruction's power, and the caster's loot

Destruction

Mastering Destruction now makes your damage spells hit harder. Online, a mastered Destruction past 100 adds to your Damage Health and Continuous Damage spells as it climbs - 1% for each point of its effective value past 100, +40% when mastered to 200. Until now those points only made spells cheaper, while the same mastery made dungeon foes tougher. Gear that raises Destruction still makes spells cheaper, as before; the extra damage comes from the mastery itself.
Spells now count the foe you are fighting when they train a mastered school. Past 100, a skill learns from tough foes, but only a weapon blow ever told it who you were fighting. A spell landing on a foe (or a foe's spell landing on you) now does too, so blasting a tough foe trains your school as fast as fighting it with a weapon. A cast never trains slower than it did before.

Potency, a new line on jewellery and weapons: +3% to +15% spell damage. Everything you wear adds up to at most +30%.
Wellspring, a new line on jewellery: 2% to 10% of your magicka back when you kill a foe, at most 10% a kill from everything you wear.
Three new caster Legendaries, found most often among mages, covens and laboratories:
- The Eye of Magnus (amulet) - Magnus's Gaze: your Destruction spells meet a saving throw 15 lower. A foe immune to the element stays immune.
- The Ring of Artaeum (ring) - Wellspring of Artaeum: 1% of your magicka returns every magic round, 2% while you are under half.
- Shalidor's Brand (broadsword, saber or longsword) - Arcane Surge: while you wield it, your Destruction spells strike 25% harder while your magicka is above three quarters.
Spell damage from loot is capped at +50% all together. None of the new spell damage reaches a fight against another player.

BAL9: Destruction's channels - a spell answers its foe, the school's climb its potency, the ladder's arcana by @Lattymoy in #851

Full Changelog: app-v0.1.8217...app-v0.1.8220