Half-Life: Alyx isn't the first full-length virtual reality game and it didn't invent many of the key VR-based mechanics at its core, but if our review of the game is anything to go off of, it's certainly one of the most refined examples. Valve has, after all, been at the forefront of VR, with its development of the HTC Vive and The Lab back in 2016. GameSpot had the chance to chat with Valve level designer Dario Casali and programmer Kerry Davis about Half-Life: Alyx and all things VR--including some of the games that helped them shape how they approach VR.

"I had a level of excitement before I started [Half-Life: Alyx], just about VR in general," Casali told GameSpot. "I was a really big fan of Budget Cuts and I flew around the Earth several times in Google Earth."

Budget Cuts is a stealth-action game from Neat Corporation. Casali cited the "full-featured interaction" players could have with the game's menacing robot antagonists and the sense of "presence" VR brings, and how both work together to raise the stakes for players, as inspirations.