Ann's option with the wizzy sounds best, it will give you the chance to die a few times and learn the ropes as well. If you max your att as well you should be able to get sb as well. Might not even be necessary since you can spellbomb the last boss anyway.

wizard, or if your doing organized tombs, I would go with a melee class, as they can be used even unmaxed with t10/t11 gear and still get sb.

Wizzy will bring you mixed emotions.

It's really easy to miss and splash another ancient with them, but you have such good range and spell bomb activity (if it comes to that) to take care of business.

But I would start there or with Necro.