diff --git a/src/ffi.c b/src/ffi.c
index 9a724fc..5717490 100644
--- a/src/ffi.c
+++ b/src/ffi.c
@@ -138,6 +138,7 @@ void hll_call(int libno, int fno)
 }
 
 extern struct static_library lib_ACXLoader;
+extern struct static_library lib_ADVSYS;
 extern struct static_library lib_AliceLogo;
 extern struct static_library lib_AliceLogo2;
 extern struct static_library lib_AliceLogo3;
@@ -171,6 +172,7 @@ extern struct static_library lib_Timer;
 
 static struct static_library *static_libraries[] = {
 	&lib_ACXLoader,
+	&lib_ADVSYS,
 	&lib_AliceLogo,
 	&lib_AliceLogo2,
 	&lib_AliceLogo3,
diff --git a/src/hll/ADVSYS.c b/src/hll/ADVSYS.c
new file mode 100644
index 0000000..62be2e0
--- /dev/null
+++ b/src/hll/ADVSYS.c
@@ -0,0 +1,40 @@
+/* Copyright (C) 2019 Nunuhara Cabbage <nunuhara@haniwa.technology>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://gnu.org/licenses/>.
+ */
+
+#include "xsystem4.h"
+#include "input.h"
+#include "hll.h"
+
+static int ADVSYS_Init(void)
+{
+	return 1;
+}
+
+static int ADVSYS_KEY_IsDown(int key)
+{
+	return key_is_down(key);
+}
+
+static int ADVSYS_SYSTEM_IsResetOnce(void)
+{
+	// TODO
+	return 0;
+}
+
+HLL_LIBRARY(ADVSYS,
+	    HLL_EXPORT(Init, ADVSYS_Init),
+	    HLL_EXPORT(KEY_IsDown, ADVSYS_KEY_IsDown),
+	    HLL_EXPORT(SYSTEM_IsResetOnce, ADVSYS_SYSTEM_IsResetOnce));
diff --git a/src/hll/SACT2.c b/src/hll/SACT2.c
index 8408a99..cedd450 100644
--- a/src/hll/SACT2.c
+++ b/src/hll/SACT2.c
@@ -439,6 +439,26 @@ HLL_WARN_UNIMPLEMENTED(0, int, SACT2, SP_GetBrightness, int sp_no);
 	    HLL_EXPORT(SP_SetBrightness, SACT2_SP_SetBrightness), \
 	    HLL_EXPORT(SP_GetBrightness, SACT2_SP_GetBrightness)
 
+static void SACTDX_SetVolumeMixerMasterGroupNum(int n)
+{
+	// TODO
+}
+
+static void SACTDX_SetVolumeMixerSEGroupNum(int n)
+{
+	// TODO
+}
+
+static void SACTDX_SetVolumeMixerBGMGroupNum(int n)
+{
+	// TODO
+}
+
+static int SACTDX_Sound_GetGroupNumFromDataNum(int n)
+{
+	return 0;
+}
+
 static int SACTDX_TRANS_Begin(int nNum)
 {
 	// TODO
@@ -458,9 +478,13 @@ static int SACTDX_TRANS_End(void)
 }
 
 #define SACTDX_EXPORTS \
-	HLL_EXPORT(TRANS_Begin, SACTDX_TRANS_Begin), \
-		HLL_EXPORT(TRANS_Update, SACTDX_TRANS_Update), \
-		HLL_EXPORT(TRANS_End, SACTDX_TRANS_End)
+	HLL_EXPORT(SetVolumeMixerMasterGroupNum, SACTDX_SetVolumeMixerMasterGroupNum), \
+	HLL_EXPORT(SetVolumeMixerSEGroupNum, SACTDX_SetVolumeMixerSEGroupNum), \
+	HLL_EXPORT(SetVolumeMixerBGMGroupNum, SACTDX_SetVolumeMixerBGMGroupNum), \
+	HLL_EXPORT(Sound_GetGroupNumFromDataNum, SACTDX_Sound_GetGroupNumFromDataNum), \
+	HLL_EXPORT(TRANS_Begin, SACTDX_TRANS_Begin),		\
+	HLL_EXPORT(TRANS_Update, SACTDX_TRANS_Update),		\
+	HLL_EXPORT(TRANS_End, SACTDX_TRANS_End)
 
 HLL_LIBRARY(SACT2, SACT_EXPORTS);
 HLL_LIBRARY(SACTDX, SACT_EXPORTS, SACTDX_EXPORTS);
diff --git a/src/meson.build b/src/meson.build
index 8095ac8..33ace4b 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -18,6 +18,7 @@ xsystem4 = ['audio.c',
             'vm.c',
 
             'hll/ACXLoader.c',
+            'hll/ADVSYS.c',
             'hll/AliceLogo.c',
             'hll/AliceLogo2.c',
             'hll/AliceLogo3.c',