Lemme do a mechanics check for a moment;
[-3] Thaumaturgy - +1 worldwalker complexity, 4 enchanted item slots
[-2] Lawbreaker 1st
[-7] +2 transformation/disruption control, +3 item frequency, +4 item power, +5 transformation/disruption complexity
[-2] +4 transformation/disruption complexity focus
OK, assuming a Lore and/or Discipline of Fantastic (given the high refresh of the game) the above build gives you enchanted items with 10 power and 4 uses/day each, and an attack roll of Legendary with them if said enchanted items deal in lethal magic. It also gives a base complexity of 17 for lethal transformation/disruption and a control of Legendary+2 for lethal spells (or just 15 complexity and legendary control for everything else). So the character could pull 25-shift rituals by just using each of his superb or fantastic skills for a skill-based aspect without any consequences and finish the ritual in 10 exchanges with minimum power used. (4 for the aspects, 1 for spell costruct, 5 for casting). Doing a 30-shift ritual would only require a couple of consequences for him and could be completed in the same casting time. When he is not doing rituals, he can still pull off standard attacks in combat using his few enchanted items. And if he has a potion slot, he could make a potion with 4 charges that stores up to four fairly big blasts; his potion complexity is only 7 lower than his ritual complexity so if he can manage a 30-shift ritual, he could make a 23-shift potion with 4 charges.
So yeah, mini-nukes are not much of a stretch for practitioners of this level.