War wiz wiz is really good at high level. With alliance at 102 you can fulminate it with one wiz merc and keep 2 healer mercs. War dru wiz probably...
If you're still set on being a tank, at the higher levels, you're going to have problems with not buying a subscription.
Most capable is going to be a plate tank paired with a CC class. Use a healer and dps merc. Leaves room for a healer or dps as a 3rd box if you want...
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