You can download for PC directly from the Official SpyParty Website or via Steam .

A standout feature that makes the game much easier to learn is the for the Sniper. The Highlight/Lowlight Feature

In a crowded party, keeping track of dozens of characters is the Sniper's biggest challenge. This feature acts as your "mental notebook":

Dims a character’s appearance. Use this for guests you’ve cleared from suspicion (e.g., they’ve been standing still for too long to be the player).

This allows you to "eliminate" the noise of the crowd, letting you focus only on the 2 or 3 guests who are still fully bright and potentially the Spy. Helpful Tips for Beginners SpyParty - A Subtle Game About Human Behavior

Marks a character with a bright outline. Use this for guests you strongly suspect of being the Spy because of a "tell"—like a weird walk or a completed mission.