Complex sentence: Not only can the player-character or objects in the game world move through portals, their momentum is conserved, allowing complex "flinging" maneuvers to be used to cross wide gaps or perform other feats to reach the exit for each test chamber.
Split into simpler sentences: Not only can the player-character or objects in the game world move through portals, their momentum is conserved. This allows complex "flinging" maneuvers to be used to cross wide gaps or perform other feats to reach the exit for each test chamber.