Klaus hid behind Ivan as the elder brother clashed with the Mastermage. This was an existential duel; the two fought with literally all their experiences, manifestations of their lives, to the death.
The Mastermage had lived a long but quiet life; his life was calcuating, defensive, and infinitely blue, meaning that, though it was transparent, you would never be able to see through to the the other side. Ivan’s life, on the other hand, was small but full of trickery. It danced around the Master Mage’s, evading the other’s ability to adapt to anything by never using the same trick twice. It was silver, and glowed too brightly to be observed for more than a moment.
Klaus couldn’t summon an existential guardian quite yet, but his life was young and unremarkable, so he imagined it would have the potency of a housecat.
His brother chipped his opponent’s life away—days spent studying, most of the age of four. But the Mastermage did not earn his title through patience. Klaus knew he was saving something deadly.