I played a DA tank at 50 before the shutdown, and it did require some substantial IO investment, but the result was by far the best Tanker experience I've had. Probably the single most important element was the Theft of Essence proc in Dark Regeneration. It was slow going in the early levels, but once you start layering some real Defense into the build and beginning to solve some of the endurance issues it takes off. Mine was DA/Elec, I've pasted the final build below. Even without really high-end items like the Gladiator'a Armor +Def IO, it was a very strong build. Even better once you start to layer Incarnate content on top of that. I'd encourage you to stick with it.
Hero Plan by Mids' Hero Designer 1.96
http://www.cohplanner.com/
Click this DataLink to open the build!
Tin Mage Mk. V: Level 50 Magic Tanker
Primary Power Set: Dark Armor
Secondary Power Set: Electrical Melee
Power Pool: Fighting
Power Pool: Speed
Power Pool: Flight
Power Pool: Leaping
Ancillary Pool: Soul Mastery
Hero Profile:
Level 1: Dark Embrace -- S'fstPrt-ResDam/Def+(A), S'fstPrt-ResKB(3), RctvArm-ResDam/EndRdx(3), RctvArm-ResDam/Rchg(5), RctvArm-ResDam/EndRdx/Rchg(5), RctvArm-ResDam(7)
Level 1: Charged Brawl -- KntkC'bat-Acc/Dmg(A), KntkC'bat-Dmg/EndRdx(7), KntkC'bat-Dmg/Rchg(9), KntkC'bat-Dmg/EndRdx/Rchg(9)
Level 2: Murky Cloud -- RctvArm-ResDam/EndRdx(A), RctvArm-ResDam/Rchg(11), RctvArm-ResDam/EndRdx/Rchg(11), RctvArm-ResDam(13), GA-3defTpProc(37)
Level 4: Death Shroud -- Erad-Acc/Dmg/Rchg(A), Erad-Acc/Dmg/EndRdx/Rchg(13), Erad-%Dam(15), C'ngBlow-Acc/Dmg(15), C'ngBlow-Dmg/EndRdx(17), C'ngBlow-Acc/Rchg(17)
Level 6: Obsidian Shield -- RctvArm-ResDam/EndRdx(A), RctvArm-ResDam/Rchg(19), RctvArm-ResDam/EndRdx/Rchg(19), RctvArm-ResDam(21), ImpArm-ResPsi(21)
Level 8: Jacobs Ladder -- Erad-Acc/Rchg(A), Erad-Acc/Dmg/Rchg(23), Erad-Acc/Dmg/EndRdx/Rchg(23)
Level 10: Taunt -- Mocking-Taunt(A), Mocking-Taunt/Rchg(25), Mocking-Taunt/Rchg/Rng(25), Mocking-Acc/Rchg(27), Mocking-Taunt/Rng(27), Mocking-Rchg(29)
Level 12: Dark Regeneration -- Sciroc-Acc/Rchg(A), Nictus-Acc/EndRdx/Heal/HP/Regen(29), Nictus-Acc/EndRdx/Rchg(31), Theft-+End%(31), Mocking-Acc/Rchg(31)
Level 14: Cloak of Darkness -- Krma-ResKB(A), LkGmblr-Def(33), LkGmblr-Rchg+(33)
Level 16: Thunder Strike -- Erad-Dmg/Rchg(A), Erad-Acc/Dmg/Rchg(34), Erad-Acc/Dmg/EndRdx/Rchg(34), Empty(40)
Level 18: Boxing -- KntkC'bat-Acc/Dmg(A), KntkC'bat-Dmg/EndRdx(36), KntkC'bat-Dmg/Rchg(36), KntkC'bat-Dmg/EndRdx/Rchg(36)
Level 20: Hasten -- RechRdx-I(A)
Level 22: Tough -- RctvArm-ResDam/EndRdx(A), RctvArm-ResDam(33), RctvArm-ResDam/Rchg(37), RctvArm-ResDam/EndRdx/Rchg(37)
Level 24: Weave -- LkGmblr-Def(A), LkGmblr-Rchg+(39), GftotA-Def/EndRdx(39), GftotA-Def(39)
Level 26: Fly -- Zephyr-ResKB(A)
Level 28: Chain Induction -- KntkC'bat-Acc/Dmg(A), KntkC'bat-Dmg/EndRdx(40), KntkC'bat-Dmg/Rchg(40), KntkC'bat-Dmg/EndRdx/Rchg(42)
Level 30: Build Up -- RechRdx-I(A)
Level 32: Oppressive Gloom -- Amaze-Stun(A), Amaze-ToHitDeb%(34), Amaze-Acc/Stun/Rchg(42), Amaze-Acc/Rchg(42), Amaze-EndRdx/Stun(43)
Level 35: Combat Jumping -- LkGmblr-Def/EndRdx(A), LkGmblr-Def(43), LkGmblr-Rchg+(45)
Level 38: Lightning Rod -- Erad-Acc/Dmg/Rchg(A), Erad-%Dam(43), Erad-Acc/Dmg/EndRdx/Rchg(45), Sciroc-Acc/Dmg/EndRdx(45), Sciroc-Dmg/EndRdx(46), SMotTanker-Rchg/Res%(46)
Level 41: Air Superiority -- KntkC'bat-Acc/Dmg(A), KntkC'bat-Dmg/EndRdx(46), KntkC'bat-Dmg/Rchg(48), KntkC'bat-Dmg/EndRdx/Rchg(48)
Level 44: Soul Tentacles -- Acc-I(A)
Level 47: Darkest Night -- HO:Enzym(A)
Level 49: Soul Transfer -- Erad-Acc/Rchg(A), Erad-Dmg/Rchg(50), Erad-Acc/Dmg/Rchg(50)
Level 1: Brawl -- Empty(A)
Level 1: Prestige Power Surge -- Empty(A)
Level 1: Prestige Power Dash -- Empty(A)
Level 1: Prestige Power Quick -- Empty(A)
Level 1: Prestige Power Rush -- Empty(A)
Level 1: Sprint -- ULeap-Stlth(A)
Level 2: Rest -- Empty(A)
Level 2: Swift -- Run-I(A)
Level 2: Hurdle -- Jump-I(A)
Level 2: Health -- Numna-Regen/Rcvry+(A), Mrcl-Rcvry+(48)
Level 2: Stamina -- EndMod-I(A), EndMod-I(50)
Level 1: Gauntlet
Level 1: Prestige Power Slide -- Empty(A)
Level 4: Ninja Run
Level 0: Freedom Phalanx Reserve
Level 0: Task Force Commander
Level 0: The Atlas Medallion
Level 0: Portal Jockey
Level 50: Void Core Final Judgement
Level 50: Diamagnetic Radial Flawless Interface
Level 50: Warworks Core Superior Ally
Level 50: Ageless Radial Epiphany
Level 50: Resilient Core Paragon
Level 50: Melee Core Embodiment
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