diff --git a/data/cdata/scripts/ending/credits.gsc b/data/cdata/scripts/ending/credits.gsc
index 81509eea..eb02ab74 100644
--- a/data/cdata/scripts/ending/credits.gsc
+++ b/data/cdata/scripts/ending/credits.gsc
@@ -3,9 +3,6 @@
 main()
 {
     replacefunc(maps\_credit_h2_autogen::_id_B775, ::initiwcredits);
-
-    // fix credits victory screen
-    replacefunc(maps\_endmission::_nextmission, ::nextmission);
 }
 
 initcredits_h2mod()
@@ -32,150 +29,3 @@ initiwcredits()
     maps\_credit_h2_autogen::initiwcredits_nerve();
     maps\_credit_h2_autogen::initiwcredits_irongalaxy();
 }
-
-nextmission(var_0)
-{
-    level notify("achievements_level_complete");
-
-    if (level.script == "ending" && level._id_AC38 != "credits_1")
-    {
-        changelevel("");
-    }
-    else
-    {
-        if (!isdefined(var_0))
-            var_0 = 0;
-
-        level notify("nextmission");
-        level.player notify("levelComplete");
-        level.nextmission = 1;
-        level.player enableinvulnerability();
-
-        if (maps\_utility::arcademode())
-        {
-            level._id_AC81 = 1;
-            thread _id_D36F::_id_AF95();
-            common_scripts\utility::flag_wait("arcademode_ending_complete");
-        }
-
-        var_1 = undefined;
-        setsaveddvar("ui_nextMission", "1");
-        setdvar("ui_showPopup", "0");
-        setdvar("ui_popupString", "");
-
-        if (level.script == "ending")
-        {
-            level.script = "af_chase";
-            nextmission(1);
-            level.script = "ending";
-        }
-
-        game["previous_map"] = level.script;
-        var_1 = level.missionsettings getlevelindex(level.script);
-
-        if (!(level.script == "af_chase" && var_0) && !maps\_utility::achievement_conditions("IMMORTAL"))
-        {
-            _func_1FC(level.script, var_1);
-            updategamerprofileall();
-            maps\_endmission::check_immortal_achievement();
-        }
-
-        maps\_gameskill::auto_adust_zone_complete("aa_main_" + level.script);
-
-        if (!isdefined(var_1))
-        {
-            missionsuccess(level.script);
-            return;
-        }
-
-        if (level.script != "ending" && !(level.script == "af_chase" && var_0))
-        {
-            level.player thread maps\_hud_util::fade_out(1, undefined);
-            soundscripts\_snd::snd_message("end_mission_fade_to_black");
-            wait 2;
-            maps\_utility::level_end_save();
-        }
-
-        if (level.script != "af_chase" || var_0)
-        {
-            level.missionsettings setlevelcompleted(var_1);
-            var_3 = maps\_endmission::updatesppercent();
-            updategamerprofile();
-
-            if (level.missionsettings hasachievement(var_1))
-                maps\_utility::giveachievement_wrapper(level.missionsettings getachievement(var_1));
-
-            if (level.missionsettings haslevelveteranaward(var_1) && getlevelcompleted(var_1) == 4 && level.missionsettings check_other_haslevelveteranachievement(var_1))
-                maps\_utility::giveachievement_wrapper(level.missionsettings getlevelveteranaward(var_1));
-
-            if (level.missionsettings hasmissionhardenedaward() && level.missionsettings getlowestskill() > 2)
-                maps\_utility::giveachievement_wrapper(level.missionsettings gethardenedaward());
-
-            level.missionsettings maps\_endmission::_id_D1B9();
-            var_4 = level.missionsettings.levels.size;
-        }
-
-        if (level.script == "af_chase" && var_0)
-            return;
-
-        if (level.script == "ending" && level._id_AC38 == "credits_1")
-            common_scripts\utility::flag_wait("af_chase_nextmission");
-
-        if (level.script == "airplane" || level.script == "ending")
-        {
-            if (level.credits_active)
-            {
-                level notify("credits_ended");
-                credits_end();
-            }
-
-            setsaveddvar("ui_nextMission", "0");
-            return;
-        }
-        else
-        {
-            var_4 = var_1 + 1;
-        }
-
-        if (getdvarint("limited_mode"))
-        {
-            setsaveddvar("ui_nextMission", "0");
-            changelevel("");
-            return;
-        }
-
-        if (maps\_utility::arcademode())
-        {
-            if (!getdvarint("arcademode_full"))
-            {
-                setsaveddvar("ui_nextMission", "0");
-                changelevel("");
-                return;
-            }
-
-            if (level.script == "cargoship")
-            {
-                changelevel("blackout", level.missionsettings getkeepweapons(var_1));
-                return;
-            }
-            else if (level.script == "airlift")
-            {
-                changelevel("village_assault", level.missionsettings getkeepweapons(var_1));
-                return;
-            }
-            else if (level.script == "jeepride")
-            {
-                changelevel("airplane", level.missionsettings getkeepweapons(var_1));
-                return;
-            }
-        }
-
-        if (level.missionsettings skipssuccess(var_1))
-        {
-            changelevel(level.missionsettings getlevelname(var_4), level.missionsettings getkeepweapons(var_1));
-            return;
-        }
-
-        missionsuccess(level.missionsettings getlevelname(var_4), level.missionsettings getkeepweapons(var_1));
-    }
-}
diff --git a/data/cdata/scripts/endmission.gsc b/data/cdata/scripts/endmission.gsc
new file mode 100644
index 00000000..d0436e79
--- /dev/null
+++ b/data/cdata/scripts/endmission.gsc
@@ -0,0 +1,171 @@
+#include maps\_endmission;
+
+main()
+{
+    // fix credits victory screen & add wait after giving mission achievements
+    replacefunc(maps\_endmission::_nextmission, ::nextmission);
+}
+
+give_mission_achievement(name)
+{
+    was_unlocked = achievementunlocked(name);
+    maps\_utility::giveachievement_wrapper(name);
+    
+    if (!was_unlocked)
+    {
+        wait 4;
+    }
+}
+
+nextmission(var_0)
+{
+    level notify("achievements_level_complete");
+
+    if (level.script == "ending" && level._id_AC38 != "credits_1")
+    {
+        changelevel("");
+    }
+    else
+    {
+        if (!isdefined(var_0))
+            var_0 = 0;
+
+        level notify("nextmission");
+        level.player notify("levelComplete");
+        level.nextmission = 1;
+        level.player enableinvulnerability();
+
+        if (maps\_utility::arcademode())
+        {
+            level._id_AC81 = 1;
+            thread _id_D36F::_id_AF95();
+            common_scripts\utility::flag_wait("arcademode_ending_complete");
+        }
+
+        var_1 = undefined;
+        setsaveddvar("ui_nextMission", "1");
+        setdvar("ui_showPopup", "0");
+        setdvar("ui_popupString", "");
+
+        if (level.script == "ending")
+        {
+            level.script = "af_chase";
+            nextmission(1);
+            level.script = "ending";
+        }
+
+        game["previous_map"] = level.script;
+        var_1 = level.missionsettings getlevelindex(level.script);
+
+        if (!(level.script == "af_chase" && var_0) && !maps\_utility::achievement_conditions("IMMORTAL"))
+        {
+            _func_1FC(level.script, var_1);
+            updategamerprofileall();
+            maps\_endmission::check_immortal_achievement();
+        }
+
+        maps\_gameskill::auto_adust_zone_complete("aa_main_" + level.script);
+
+        if (!isdefined(var_1))
+        {
+            missionsuccess(level.script);
+            return;
+        }
+
+        if (level.script != "ending" && !(level.script == "af_chase" && var_0))
+        {
+            level.player thread maps\_hud_util::fade_out(1, undefined);
+            soundscripts\_snd::snd_message("end_mission_fade_to_black");
+            wait 2;
+            maps\_utility::level_end_save();
+        }
+
+        if (level.script != "af_chase" || var_0)
+        {
+            level.missionsettings setlevelcompleted(var_1);
+            var_3 = maps\_endmission::updatesppercent();
+            updategamerprofile();
+
+            if (level.missionsettings hasachievement(var_1))
+            {
+                give_mission_achievement(level.missionsettings getachievement(var_1));
+            }
+
+            if (level.missionsettings haslevelveteranaward(var_1) && getlevelcompleted(var_1) == 4 && level.missionsettings check_other_haslevelveteranachievement(var_1))
+            {
+                give_mission_achievement(level.missionsettings getlevelveteranaward(var_1));
+            }
+
+            if (level.missionsettings hasmissionhardenedaward() && level.missionsettings getlowestskill() > 2)
+            {
+                give_mission_achievement(level.missionsettings gethardenedaward());
+            }
+
+            level.missionsettings maps\_endmission::_id_D1B9();
+            var_4 = level.missionsettings.levels.size;
+        }
+
+        if (level.script == "af_chase" && var_0)
+            return;
+
+        if (level.script == "ending" && level._id_AC38 == "credits_1")
+            common_scripts\utility::flag_wait("af_chase_nextmission");
+
+        if (level.script == "airplane" || level.script == "ending")
+        {
+            if (level.credits_active)
+            {
+                level notify("credits_ended");
+                credits_end();
+            }
+
+            setsaveddvar("ui_nextMission", "0");
+            return;
+        }
+        else
+        {
+            var_4 = var_1 + 1;
+        }
+
+        if (getdvarint("limited_mode"))
+        {
+            setsaveddvar("ui_nextMission", "0");
+            changelevel("");
+            return;
+        }
+
+        if (maps\_utility::arcademode())
+        {
+            if (!getdvarint("arcademode_full"))
+            {
+                setsaveddvar("ui_nextMission", "0");
+                changelevel("");
+                return;
+            }
+
+            if (level.script == "cargoship")
+            {
+                changelevel("blackout", level.missionsettings getkeepweapons(var_1));
+                return;
+            }
+            else if (level.script == "airlift")
+            {
+                changelevel("village_assault", level.missionsettings getkeepweapons(var_1));
+                return;
+            }
+            else if (level.script == "jeepride")
+            {
+                changelevel("airplane", level.missionsettings getkeepweapons(var_1));
+                return;
+            }
+        }
+
+        if (level.missionsettings skipssuccess(var_1))
+        {
+            changelevel(level.missionsettings getlevelname(var_4), level.missionsettings getkeepweapons(var_1));
+            return;
+        }
+
+        missionsuccess(level.missionsettings getlevelname(var_4), level.missionsettings getkeepweapons(var_1));
+    }
+}
diff --git a/src/client/component/achievements.cpp b/src/client/component/achievements.cpp
index 168981c1..82b52a05 100644
--- a/src/client/component/achievements.cpp
+++ b/src/client/component/achievements.cpp
@@ -8,6 +8,8 @@
 #include "scheduler.hpp"
 #include "command.hpp"
 
+#include "gsc/script_extension.hpp"
+
 #include "game/ui_scripting/execution.hpp"
 
 #include <utils/hook.hpp>
@@ -268,6 +270,21 @@ namespace achievements
 				get_achievements(&file);
 				give_achievement_id_internal(&file, id);
 			});
+
+			gsc::add_function("achievementunlocked", []()
+			{
+				const auto name = game::Scr_GetString(0);
+				const auto id = get_achievement_id(name);
+				if (!id.has_value())
+				{
+					game::Scr_AddInt(0);
+					return;
+				}
+
+				achievement_file_t file{};
+				get_achievements(&file);
+				game::Scr_AddInt(has_achievement(&file, id.value()));
+			});
 		}
 	};
 }