Instances

Each game is its own instance — an isolated folder with a specific modpack, mods, settings and Java. Instances don't affect each other, so you can keep vanilla, a heavy modpack and a test copy side by side.

• Grid or list, sorting and quick search.
• Groups (folders) — create, rename, delete, drag & drop an instance in.
• Until you have a group, packs sit loose. A group heading appears once you make at least one folder.
• Card size S / M / L with consistent scale.
• Cards show the modpack logo (CurseForge/Modrinth) or a custom icon you give the instance.
• Import .mrpack / CurseForge zip, also by dragging a file into the library; instances from other launchers are in Modpacks & mods.

New instance. You pick the Minecraft version from a list you can search: the latest release is on top, snapshots and old beta/alpha versions are switches. The loader (Fabric, Quilt, NeoForge, Forge) and its version are offered only from what really exists for the chosen Minecraft version, with the newest stable one as the default. Offline, the dialog shows the last saved list. If you would rather type the versions yourself, tick Type the versions by hand (an advanced option, with no checking).

Open an instance for a page of its own: status, worlds, screenshots (a gallery), servers, mods, logs, Performance, Presets and settings. Performance measures how the pack runs on your PC (Performance and the benchmark); Presets apply a pack author's settings in one click and revert them (Presets). The key part is per-instance settings that override the global ones:

• RAM — how much memory the instance gets. The default is Auto: for instances with mods 75 % of the computer's RAM (up to 12 GB; at least 3 GB always stay for the system), while plain Minecraft stays at 2–3 GB. Memory you set yourself is not changed; the Auto button brings the default back. The fix after a memory crash may raise it only up to the same ceiling.
• Backups — a backup is made before a pack update and going back is one click; the last 5 are kept (see Modpacks & mods).
• Java — which version to use (the launcher manages it, see Troubleshooting).
• JVM args — the default set is Recommended (worked out for the Java that actually runs the game); your own flags stay as you wrote them.
• On Linux a wrapper (such as gamemoderun, mangohud) and environment variables at launch.
• Potato Mode is, from 0.11, also a built-in preset in the Presets tab (preview, backup, Revert); the older experimental switch in instance settings is turned on in Settings → About.

• Clone instance — duplicate it in one click and test mods without breaking the original.
• File check — the launcher compares mods (SHA-1) with what belongs to the instance and repairs what is missing or damaged. It knows which folder a file belongs in, so resource packs and shaders are not reported missing.

Deleting an instance removes the DB row and the on-disk folder — clean and complete.

• World management — backup/restore of a single world.
• Advanced groups — colors, cross-group sorting, pin.