I am frustrated due to not being able to complete this quest due to not being able to find a team. Actually, I have been on numerous teams but none worked because we did not have a death person. I do not think it was really thought through very well when to complete this battle you HAVE to have a death person, fire or storm person.
Balance, Ice and Myth get overlooked quite often. Bottom line, I have not been able to finish this quest in quite a while because of not having a death person or being selected for a team. I would like to be able to continue this game. Perhaps KI can re-think this through so all wizards can complete it with whatever wilzards are available.
I ran into the same problem, so I soloed. Shockingly, it is possible to solo this battle if you have extreme resist, heals, shields, some Monstrology minions (or crowns henchmen) and a lot of patience.
Eric Stormbringer did this using a Monstrology "Pill Ghost" minion from the Pacman battle in Mirage. The Pill Ghosts have perfect resist. I'm putting the link in but if it's not allowed to link to an outside site, just Google "Eric Stormbringer solo titan" and you should find his post at Final Bastion. (That's a Wizard101 fan site.)
I adapted his strategy and soloed on both a Balance and a Fire. What I did was use Jade gear and a pet that has max resist plus may-cast heals. I packed Brace AND Tower Shields in the side deck. My main deck had heals and I relied on the minions to dole out damage by chipping away the Titan's health little by little. When the Titan raises the trident, you have two turns to put up Brace and Tower, which should get your resist high enough to survive the attack when he puts it back down. My Balance had a slightly easier time than my Fire did, but both got through it after a very long slog.
It is possible to get through it on a well coordinated team even if there's no Death. The key, again, is communication and everyone packs TOWER SHIELD plus BRACE in their side deck for when the triton raises up his trident. If you can coordinate attacks quickly enough, you might even avoid the trident altogether.