Not really sure why people keep saying dark mind is drks only tool for magic DMG. Grit, shadow skin and shadow wall all work for mitigation against all sources of DMG including mag DMG. If you're lucky enough for reprisal, that's another 10% less. The only tank skill that is useless for mag DMG in drks arsenal is dark dance. (No idea why if drks focus was mag DMG, why the devs gave drk this skill. Sounds like they need to look at ffxi rune fencer for some ideas.)

Pld has: shield oath, sentinel, rampart, and hallowed (only works on very certain attacks..though I have used to mitigate some mag DMG). Awareness works against all forms of crits including mag DMG.

War has: inner beast, vengeance, and storms path (10% like reprisal). If you want to count ehp they also got defiance and thrill.