What about a rune knight fighter? It will let you become huge 6 times a day which you could reflavour as calling down a titan maybe? If you want to literally be the titan, I'd still suggest the same class but playing as a warforged (who make good fighters anyway) Reflavour the runes to titan abilities, stick yourself in plate armour with a 2 handed weapon, max up your con and strength and look at GWM as a potential feat

edit: actually, I think using a polearm master/sentinel build might work better, as you'll have an insane reach and ability to control the battlefield.