Pike, along with the rest of Keegan's squad were forced to jump out of the C-47 early as it was hit with anti-aircraft fire. He fought alongside the rest of the squad throughout Off Target and Der Bunker, after capturing the bunker, he moved 20 miles west to regroup with the rest of the 82nd Division.
Harrison Pike, along with Chalmers and Slauson were assigned to parachute out of a C-47 for Operation Neptune, he was not present when Keegan's glider crashed. Pike fought along with the rest of his squad until Keegan and Garrett regrouped with them. Pike, as well as the rest of the squad then rescued Sergeant Magnusson from the church after he was captured by nazis, they then defended the church from a German counter-attack until it seemed as if all of them were wiped out. When Keegan went downstairs to open the door to exit the church, a lone Fallschirmjager incapacitated him with a buttstroke from a Karabiner 98K. After Keegan recovered, they moved through the cemetery, clearing out any German soldiers within. After Pike and the squad reached the first bridge and destroyed it, Keegan and Garrett split from Sergeant Magnusson's squad to search for a Bazooka, Pike stayed with Sergeant Magnusson's squad to search for more bridges to destroy. Pike also fought throughout the mission Requiem, after Keegan was incapacitated by an explosive charge detonating early.
Pike was part of Keegan's unit during Operation Market Garden. In A Shallow Grave he, alongside the squad, fought their way towards and captured the fortified house. Pike and the rest of Keegan's squad then cleared out the farmhouse and windmill behind the house, inside the farmhouse the squad found and secured some maps. Garrett then heard German soldiers outside and translated what they were saying, the squad then ambushed them. Pike was also present in Haunted where he, along with the squad defended a house from German infantry, cleared out a bunker and fought their way across a bridge and destroyed two Anti-Air Guns. After moving to Grave, Pike and the squad came under fire from a German ambush, after dealing with the ambush they then moved through the town, clearing out any resistance they encountered. Shortly after the ambush they came a across a Tiger Tank, with no anti-tank weapons around, however the Bazooka Operator, who was nearby destroyed the tank. The squad then continued to move through grave until they came across a second tiger tank, which was destroyed by Keegan, but not before it killed Chalmers.
Pike was part of Keegan's squad in Operation Varsity. In Endgame he fought his way through the beaches along with Keegan and the rest of the squad. After Keegan destroyed the Flak 88, they were pinned down in a farmhouse by MG42s, forcing them to defend it from German infantry trying to retake it. Aftewards they moved through the trenches, clearing out German resistance along the way and destroying more Flak 88s. At the end of the mission Pike and the rest of his squad split up from Keegan, who was then joined by a different squad. Pike was present in the squad led by Garrett that appears halfway through The Crucible, where they mow down a cornered squad of German soldiers with ease, they then regroup with Keegan. The squad advances upstairs however Garrett notices how there are probably snipers in the next area, one soldier does not believe Garrett and then gets killed by a sniper. Pike, and the rest of the squad stay behind as Keegan clears the area of snipers. After the snipers are cleared Pike and the squad regroup with Keegan where they defend the factory against a final assault from German infantry and tanks.