diff --git a/src/core/arguments.ts b/src/core/arguments.ts
index 85dd331..9382f94 100644
--- a/src/core/arguments.ts
+++ b/src/core/arguments.ts
@@ -1,17 +1,18 @@
 import path from "path";
 import { isNeeded } from "../utils/rules";
-import { Argument, Auth, PoolFile, Version } from "../utils/types";
+import { Argument, Auth, Version } from "../utils/types";
 import { getLibraries } from "./libraries";
 import { version as packageVersion } from "../../package.json";
 import { getArgument } from "./log4j";
 
+// Fill templates
 function fillArguments(
   arg: string,
   versionManifest: Version,
   assetsPath: string,
   instancePath: string,
   librariesPath: string,
-  classPaths: PoolFile[],
+  classPaths: string,
   auth: Auth,
 ) {
   const argumentsToFill = {
@@ -25,6 +26,7 @@ function fillArguments(
     "${version_type}": versionManifest.type,
     "${assets_index_name}": versionManifest.assets,
     "${assets_root}": assetsPath,
+    "${game_assets}": assetsPath,
     "${auth_access_token}": auth.access_token,
     "${auth_session}": auth.access_token,
     "${auth_player_name}": auth.name,
@@ -44,11 +46,10 @@ function fillArguments(
     }
   }
 
-  console.log(arg)
-
   return arg;
 }
 
+// Check if each arg is needed and fill templates
 function parseArg(
   this: string[],
   arg: Argument,
@@ -56,7 +57,7 @@ function parseArg(
   assetsPath: string,
   instancePath: string,
   librariesPath: string,
-  classPaths: PoolFile[],
+  classPaths: string,
   auth: Auth,
 ) {
   if (isNeeded(arg)) {
@@ -133,16 +134,15 @@ export async function generateLaunchArguments(
     customGameArgs?: string;
   },
 ) {
-  // Log4j /!\
-  // Replace templates /!\
-
   const jvm: string[] = [];
-  const game: string[] = [];
+  let game: string[] = [];
+
+  const versionJar = path.join(versionRoot, `${versionManifest.id}.jar`);
 
   const classPaths = generateClassPaths(
     versionManifest,
     librariesPath,
-    path.join(versionRoot, `${versionManifest.id}.jar`),
+    versionJar,
   );
 
   function p(args: string[], arg: Argument) {
@@ -157,11 +157,33 @@ export async function generateLaunchArguments(
     ]);
   }
 
-  for (const arg of versionManifest.arguments.jvm) {
-    p(jvm, arg);
-  }
-  for (const arg of versionManifest.arguments.game) {
-    p(game, arg);
+  if (versionManifest.arguments) {
+    for (const arg of versionManifest.arguments.jvm) {
+      p(jvm, arg);
+    }
+    for (const arg of versionManifest.arguments.game) {
+      p(game, arg);
+    }
+  } else {
+    console.log(versionManifest.minecraftArguments)
+    game = fillArguments(
+      versionManifest.minecraftArguments,
+      versionManifest,
+      assetsPath,
+      instancePath,
+      librariesPath,
+      classPaths,
+      auth,
+    ).split(" ");
+
+    jvm.push(`-Djava.library.path=${path.join(instancePath, "natives")}`);
+    jvm.push(`-Dminecraft.launcher.brand=nlk`);
+    jvm.push(`-Dminecraft.launcher.version=${packageVersion}`);
+    jvm.push(
+      `-Dminecraft.client.jar=${path.join(versionRoot, `${versionManifest.id}.jar`)}`,
+    );
+    jvm.push("-cp");
+    jvm.push(classPaths)
   }
 
   if (options.customJvmArgs !== "") {
@@ -178,21 +200,26 @@ export async function generateLaunchArguments(
 
   const log4j = await getArgument(versionManifest, versionRoot);
 
+  let launchArguments = [
+    ...jvm,
+    `-Xms${options.minRam || "2G"}`,
+    `-Xmx${options.maxRam || "2G"}`,
+    "-XX:+UnlockExperimentalVMOptions",
+    "-XX:+UseG1GC",
+    "-XX:G1NewSizePercent=20",
+    "-XX:G1ReservePercent=20",
+    "-XX:MaxGCPauseMillis=50",
+    "-XX:G1HeapRegionSize=32M",
+  ]
+
+  if (log4j) {
+    launchArguments.push(log4j)
+  }
+
+  launchArguments = [...launchArguments, versionManifest.mainClass, ...game,]
+
   return {
     command: javaExecutable,
-    args: [
-      ...jvm,
-      `-Xms${options.minRam || "2G"}`,
-      `-Xmx${options.maxRam || "2G"}`,
-      "-XX:+UnlockExperimentalVMOptions",
-      "-XX:+UseG1GC",
-      "-XX:G1NewSizePercent=20",
-      "-XX:G1ReservePercent=20",
-      "-XX:MaxGCPauseMillis=50",
-      "-XX:G1HeapRegionSize=32M",
-      log4j,
-      versionManifest.mainClass,
-      ...game,
-    ],
+    args: launchArguments,
   };
 }
diff --git a/src/core/launch.ts b/src/core/launch.ts
index 4c14239..b199dd9 100644
--- a/src/core/launch.ts
+++ b/src/core/launch.ts
@@ -1,5 +1,5 @@
 import { version as packageVersion } from "../../package.json";
-import { spawn } from "child_process";
+import { spawn, spawnSync } from "child_process";
 import { LaunchArguments } from "../utils/types";
 
 export function launch(
@@ -11,6 +11,7 @@ export function launch(
   console.log(
     `[nlk ${packageVersion}] Launching command : ${launchArguments.command} ${launchArguments.args.join(" ")}`,
   );
+
   const process = spawn(launchArguments.command, launchArguments.args, {
     detached,
     cwd: gameRoot,
diff --git a/src/core/libraries.ts b/src/core/libraries.ts
index 5f87afe..3a04be9 100644
--- a/src/core/libraries.ts
+++ b/src/core/libraries.ts
@@ -9,7 +9,7 @@ export function getLibraries(versionManifest: Version, librariesRoot: string) {
   for (const key in versionManifest.libraries) {
     if (Object.prototype.hasOwnProperty.call(versionManifest.libraries, key)) {
       const library = versionManifest.libraries[key];
-      if (isNeeded(library)) {
+      if (isNeeded(library) && library.downloads.artifact) {
         libs.push({
           url: library.downloads.artifact.url,
           path: path.join(librariesRoot, library.downloads.artifact.path),
diff --git a/src/core/log4j.ts b/src/core/log4j.ts
index fedc2fe..5778564 100644
--- a/src/core/log4j.ts
+++ b/src/core/log4j.ts
@@ -5,37 +5,42 @@ import { exists } from "../utils/fs";
 import { hash } from "crypto";
 import fs from "fs/promises";
 
-async function patchFileLog4j(versionManifest: Version, xmlDestination: string) {
-  const original = await fs.readFile(xmlDestination, {encoding: "utf-8"})
+async function patchFileLog4j(xmlDestination: string) {
+  const original = await fs.readFile(xmlDestination, { encoding: "utf-8" })
   await fs.writeFile(xmlDestination, original.replace("<LegacyXMLLayout />", ""))
 }
 
 export async function getArgument(
   versionManifest: Version,
   destination: string,
-) {
-  const xmlDestination = path.join(
-    destination,
-    versionManifest.logging.client.file.id,
-  );
-  if (!(await exists(xmlDestination))) {
-    await downloadFile({
-      url: versionManifest.logging.client.file.url,
-      path: xmlDestination,
-    });
+): Promise<string | null> {
+  if (versionManifest.logging?.client) {
+    const xmlDestination = path.join(
+      destination,
+      versionManifest.logging.client.file.id,
+    );
+    if (!(await exists(xmlDestination))) {
+      await downloadFile({
+        url: versionManifest.logging.client.file.url,
+        path: xmlDestination,
+      });
 
-    if (
-      hash("sha1", await fs.readFile(xmlDestination, { encoding: "utf-8" })) !==
-      versionManifest.logging.client.file.sha1
-    ) {
-      throw new Error("Wrong hash for log4j's xml config");
+      if (
+        hash("sha1", await fs.readFile(xmlDestination, { encoding: "utf-8" })) !==
+        versionManifest.logging.client.file.sha1
+      ) {
+        throw new Error("Wrong hash for log4j's xml config");
+      }
+
+      await patchFileLog4j(xmlDestination)
+
+      return versionManifest.logging.client.argument.replace(
+        "${path}",
+        xmlDestination,
+      );
     }
-
-    await patchFileLog4j(versionManifest, xmlDestination)
   }
-
-  return versionManifest.logging.client.argument.replace(
-    "${path}",
-    xmlDestination,
-  );
+  
+  // if logging is not present it means that the verson is older than 1.7 hence the fix for log4j isn't needed
+  return null
 }
diff --git a/src/launcher/instance.ts b/src/launcher/instance.ts
index 76b2079..38fafe5 100644
--- a/src/launcher/instance.ts
+++ b/src/launcher/instance.ts
@@ -8,7 +8,6 @@ import {
 } from "../utils/types";
 import * as core from "../core";
 import path from "path";
-import { os, arch } from "../utils/systemInfo";
 import { EventEmitter } from "node:events";
 import { InstallError, LaunchError } from "../utils/errors";
 import { installForge } from "../core/modloaders";
@@ -149,7 +148,7 @@ export class Instance extends EventEmitter<InstanceEvents> {
 
     try {
       const nativesDownloader = await core.NativesDownloader(
-        this.instanceLocation,
+        path.join(this.instanceLocation, "natives"),
         this.versionManifest,
       );
       nativesDownloader.on("completed", () => {
diff --git a/src/utils/types.ts b/src/utils/types.ts
index 352486c..28664e8 100644
--- a/src/utils/types.ts
+++ b/src/utils/types.ts
@@ -116,10 +116,11 @@ export type Library = {
 };
 
 export type Version = {
-  arguments: {
+  arguments?: {
     game: Argument[];
     jvm: Argument[];
   };
+  minecraftArguments: string;
   assetIndex: {
     id: string;
     sha1: string;
@@ -141,7 +142,7 @@ export type Version = {
     majorVersion: number;
   };
   libraries: Library[];
-  logging: {
+  logging?: {
     client: {
       argument: string;
       file: { id: string; sha1: string; size: number; url: string };
diff --git a/src/utils/unzip.ts b/src/utils/unzip.ts
index e30e799..711cf12 100644
--- a/src/utils/unzip.ts
+++ b/src/utils/unzip.ts
@@ -11,7 +11,6 @@ export function unzipAll(from: string, to: string, filters: string[]) {
     for (const filter of filters) {
       if (entry.entryName.includes(filter)) {
         shouldSkip = true;
-        console.log("skipping", entry.entryName);
       }
     }
     if (shouldSkip) continue;
diff --git a/tests/instance/modloaders/oldForge.test.ts b/tests/instance/modloaders/oldForge.test.ts
new file mode 100644
index 0000000..2bb6334
--- /dev/null
+++ b/tests/instance/modloaders/oldForge.test.ts
@@ -0,0 +1,49 @@
+import { test } from "vitest";
+import { Instance, offlineAuth, RuntimeManager, getJavaComponent } from "../../../dist/index.js";
+import path from "path";
+import fs from "fs/promises";
+
+const gameRoot = path.join(import.meta.dirname, "..", "temp");
+await fs.rm(gameRoot, { recursive: true, force: true });
+await fs.mkdir(gameRoot, { recursive: true });
+
+test("launch game", { timeout: 0 }, async () => {
+  const instance = new Instance();
+  const javaManager = new RuntimeManager(path.join(gameRoot, "java"));
+
+  javaManager.on("progress", console.log)
+
+  const java = await javaManager.use(await getJavaComponent("1.12.2"))
+
+  const auth = offlineAuth("player");
+
+  instance.setVersion("1.12.2");
+  instance.setPaths(gameRoot);
+  instance.setAuth(auth);
+  instance.setJavaExecutable(java)
+  instance.setModLoader("forge", "14.23.5.2864");
+
+  instance.on("progress", console.log);
+
+  await instance.install();
+  const p = await instance.launch();
+
+  p.stdout.on("data", (d: Buffer) => {
+    console.log(d.toString());
+  });
+
+  p.stderr.on("data", (d: Buffer) => {
+    console.log(d.toString());
+  });
+
+  await new Promise<void>((res) => {
+    p.on("error", (d: Buffer) => {
+      console.log(d.toString());
+      res();
+    });
+    p.on("close", () => {
+      console.log("closed");
+      res();
+    });
+  });
+});