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When a large force of Fallen, including a Ketch, was discovered in the Tescan Valley, Hassa went with Rezyl Azzir and Tover to assault the Fallen. Taking position on a slope above the Fallen, the three Guardians fired rockets at two scouting Skiffs, driving one away and drawing the other Skiffs in in to attack. Hassa and Tover were ordered to leave by Azzir and draw the Skiffs away, causing Hassa, who worried about Azzir's safety while also being envious of his plans, to laugh and declare he could not fight a whole Ketch by himself. The legendary Guardian replied that his target was not the Ketch and repeated his order, which Hassa and Tover obeyed by leaving on their Sparrows and drawing the Skiffs after them.
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