You can make (almost) one-way glass with tinted glass. : r/Minecraft
FORGE] [1.4.7] [UPDATED] The Spy Glass Mod, SNEEKY 1 WAY GLASS ! UPDATED AND AWESOME! - Minecraft Mods - Mapping and Modding: Java Edition - Minecraft Forum - Minecraft Forum
FORGE] [1.4.7] [UPDATED] The Spy Glass Mod, SNEEKY 1 WAY GLASS ! UPDATED AND AWESOME! - Minecraft Mods - Mapping and Modding: Java Edition - Minecraft Forum - Minecraft Forum
You can make (almost) one-way glass with tinted glass. : r/Minecraft
How to Get One-sided Glass in Minecraft (Vanilla) - YouTube
One Way Glass Minecraft Bedrock and Java NO MODS - (Mobile, Consoles, PC) - YouTube