Prismarine V4.2a is a release file of the Minecraft shader Prismarine Shader, made for Minecraft 1.17.1, 1.19-Snapshot, 1.16.5, 1.18.2, 1.15.2. It was published on May 10, 2022 and is 0.6 MB in size. For the full description, screenshots and every other version, visit the Prismarine Shader shader page.
How to install: Put the .zip into .minecraft/shaderpacks (do not extract it) and select it under Options → Video Settings → Shader Packs. Needs Iris or OptiFine.