Episode 2 took the core gameplay and engine of Half-Life 2 and moved it to a bigger, more open world. It’s essentially a giant road trip and you, as Gordon Freeman, are free to go as fast or Subscribe to the world's #1 PC gaming mag; etc all now open by pressing E once or twice". (the mod currently uses the Half-Life 2 HUD), hand-animations for interacting with weapons and R3A4p.