After the elevator ride, during the large "forced" fight where you defend Foxtrot, drop off the left side and run along the cliff edge, killing the 4 hybrids in your way (to alleviate pressure). After ducking under the VTOL wing, run directly (you'll be at a diagonal angle) across the gap, DO NOT run into the canyon! This will make the hybrids on the wall fire at you and miss. Then simply run into the canyon ready to kill the three chameleons. Be careful to not die to the enemies after this as you wont have a checkpoint till after the Titan dies.

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