So in an epic level match up, how do you kill two high level casters (one arcane, one mystic theurge) using a epic paladin and his retinue of clerics, iquisitors, and the like. The paladin rides a redeemed mythic red dragon (cr 23 from mythic adventures) and is a graveknight, and lord of a massive country (think height of Roman Empire) He is lvl 23, and mythic 2, his entourage is 5 20 level divine casters or martial characters of undetermined class.
Start by finding whatever demi-planes the caster's have hidden their clones and real bodies in.
Defeating them should be somewhat simpler given what could be done with epic rules. Have your dragon teleport within melee range and go to town.