The laser of the robot's weapon gets eaten as they make contact with the shielding, momentarily making its presence known in the portions that absorb the damage. Luckily it's 'effective' only on blocking whatever's coming from outside its sphere, Zechs movements and own weaponry not inhibited by the magic.

And Tidus isn't inhibited either from joining in on the action.

Sentry guards scatter around their destination, fenced in by wire framing and years of jungle overgrowth. Awoken by the activity of unknown, their biological coding different enough from the animals that lurk the jungle to bring the bots whirring into life. Zechs's target goes down, the rust of inactivity and the climate left untreated sunk into the joints of all of the sentry robots. But it doesn't make them relentless, as the others awoken circle around to find the infiltrators. Coming round from two sides--

Tidus is ready with a new spell, flipping out of the fire of fire shots for the two he has his eyes set on, better prepared. Flinging out the hand, a bolt of electricity crashes down from overhead, shuddering through the metallic bodies even after the fact.

let's kick some robot butt.