Delan left for Horizon because he believed that the Systems Alliance brought nothing but trouble. He felt that his claims were justified when the Alliance started setting up GARDIAN anti-ship batteries on the colony for defense against probable Cerberus attacks, seeing that they only made Horizon a target. Worse, the targeting calibration was completely off, so the Alliance sent a representative to help fix the problem. When the communications went down, the Collectors, originally believed to be myths, attacked. Delan hid in a shed as the Collectors began paralyzing and rounding up every human in sight.
When the Normandy SR-2 responds to the attack, Commander Shepard finds Delan hiding in one of the buildings. Delan can be advised to stay put, letting Shepard power up the defense towers to take out the Collector ship. However, even if asked to help Shepard, Delan will reject the offer, saying that a mechanic can do nothing against Collectors. Unfortunately, the Collectors escape with approximately one-third of Horizon's colonists. A dismayed Delan runs out, concerned over the loss of his friends and loved ones. Things get even more disappointing for Delan when one of Shepard's former squadmates appears, not having been kidnapped. Having had enough of the Alliance, Delan walks away.
- It is possible to "kill" Delan. If fired upon by the M-100 Grenade Launcher or the ML-77 Missile Launcher or the M-920 Cain, he will "die". His body is nowhere to be found, all there is, is a black mark from where the weapon's round hit, which is where Delan stood. When the shot impacts on Delan, he will disappear, but he will still show up at the end of the level.