diff --git a/src/controllers/api/nemesisController.ts b/src/controllers/api/nemesisController.ts
index abd9180e..95c9ab66 100644
--- a/src/controllers/api/nemesisController.ts
+++ b/src/controllers/api/nemesisController.ts
@@ -153,13 +153,13 @@ export const nemesisController: RequestHandler = async (req, res) => {
             if (passcode[body.position] != body.guess) {
                 res.end();
             } else {
-                inventory.Nemesis!.Rank += 1;
-                inventory.Nemesis!.InfNodes = getInfNodes(
-                    getNemesisManifest(inventory.Nemesis!.manifest),
-                    inventory.Nemesis!.Rank
-                );
-                await inventory.save();
-                res.json({ RankIncrease: 1 });
+                const manifest = getNemesisManifest(inventory.Nemesis!.manifest);
+                if (inventory.Nemesis!.Rank + 1 < manifest.systemIndexes.length) {
+                    inventory.Nemesis!.Rank += 1;
+                    inventory.Nemesis!.InfNodes = getInfNodes(manifest, inventory.Nemesis!.Rank);
+                    await inventory.save();
+                    res.json({ RankIncrease: 1 });
+                }
             }
         }
     } else if ((req.query.mode as string) == "rs") {