diff --git a/game/overlord/jak3/iso.cpp b/game/overlord/jak3/iso.cpp
index e7ec44cd2..265ef9aeb 100644
--- a/game/overlord/jak3/iso.cpp
+++ b/game/overlord/jak3/iso.cpp
@@ -3,9 +3,9 @@
 #include <cstring>
 
 #include "common/log/log.h"
+#include "common/util/Assert.h"
 
 #include "game/common/dgo_rpc_types.h"
-#include "game/overlord/common/isocommon.h"
 #include "game/overlord/jak3/basefilesystem.h"
 #include "game/overlord/jak3/iso_api.h"
 #include "game/overlord/jak3/iso_fake.h"
@@ -34,7 +34,11 @@ static int s_nDGOMbx;
 
 static u32 DGOThread();
 u32 ISOThread();
-int NullCallback(ISO_Msg* msg);
+int NullCallback(ISO_Hdr* msg);
+int CopyDataToEE(ISO_Hdr*);
+int CopyDataToIOP(ISO_Hdr*);
+int CopyDataTo989snd(ISO_Hdr*);
+int CopyData(ISO_LoadSingle*, int);
 
 /* COMPLETE */
 void InitDriver() {
@@ -158,14 +162,78 @@ u32 ISOThread() {
       msg->file = nullptr;
       msg->callback = NullCallback;
 
-      switch (msg->msg_kind) {
-        case LOAD_TO_EE_CMD_ID:
-        case LOAD_TO_IOP_CMD_ID:
-        case LOAD_TO_EE_OFFSET_CMD_ID:
+      /* LoadSingle messages */
+      if (msg->msg_kind >= LOAD_TO_EE_CMD_ID && msg->msg_kind <= LOAD_TO_989SND) {
+        auto* ls = static_cast<ISO_LoadSingle*>(msg);
+        int pri = 0;
+        if (ls->unk40 == 2) {
+          pri = 2;
+        }
+        if (ls->unk40 == 10) {
+          pri = 4;
+        }
+        if (!QueueMessage(msg, pri)) {
           break;
-        default:
-          lg::error("unhandled iso msg type {:x}", msg->msg_kind);
+        }
+
+        msg->file = nullptr;
+        if (msg->msg_kind == LOAD_TO_EE_OFFSET_CMD_ID) {
+          msg->file = g_pFileSystem->Open(ls->fd, ls->offset, EFileComp::MODE1);
+        } else if (msg->msg_kind == LOAD_TO_989SND) {
+          char name[16] = {0};
+          if (ls->filename) {
+            strncpy(name, ls->filename, 12);
+            name[8] = 0;
+            strcat(name, ".sbk");
+            auto fd = g_pFileSystem->Find(name);
+            if (fd) {
+              msg->file = g_pFileSystem->Open(ls->fd, -1, EFileComp::MODE1);
+            }
+          }
+        } else {
+          msg->file = g_pFileSystem->Open(ls->fd, -1, EFileComp::MODE1);
+        }
+
+        if (!msg->file) {
+          msg->m_nStatus = 8;
+          UnqueueMessage(msg);
+          ReturnMessage(msg);
           break;
+        }
+
+        ls->unk44 = ls->address;
+        ls->unk48 = 0;
+        ls->length_to_copy = g_pFileSystem->GetLength(ls->fd);
+        if (msg->msg_kind == LOAD_TO_989SND) {
+          ls->length = ls->length_to_copy;
+        } else {
+          if (!ls->length_to_copy || ls->length < ls->length_to_copy) {
+            ls->length_to_copy = ls->length;
+          }
+        }
+
+        switch (msg->msg_kind) {
+          case LOAD_TO_EE_CMD_ID:
+            msg->callback = CopyDataToEE;
+            break;
+          case LOAD_TO_IOP_CMD_ID:
+            msg->callback = CopyDataToIOP;
+            break;
+          case LOAD_TO_EE_OFFSET_CMD_ID:
+            msg->callback = CopyDataToEE;
+            break;
+          case LOAD_TO_989SND:
+            msg->callback = CopyDataTo989snd;
+            break;
+          default:
+            ASSERT_NOT_REACHED();
+        }
+
+        msg->m_nStatus = 2;
+        msg->SetActive(true);
+      } else if (msg->msg_kind == 0xADEADBEE) {
+        ReturnMessage(msg);
+        ExitThread();
       }
     }
 
@@ -221,13 +289,19 @@ static void ISO_LoadDGO(RPC_Dgo_Cmd* msg) {
     return;
   }
 
+  ASSERT_NOT_REACHED();
+
   msg->buffer1 = msg->buffer_heap_top;
   msg->result = 0;
 }
 
-static void ISO_LoadNextDGO(RPC_Dgo_Cmd* msg) {}
+static void ISO_LoadNextDGO(RPC_Dgo_Cmd* msg) {
+  ASSERT_NOT_REACHED();
+}
 
-static void ISO_CancelDGO(RPC_Dgo_Cmd* msg) {}
+static void ISO_CancelDGO(RPC_Dgo_Cmd* msg) {
+  ASSERT_NOT_REACHED();
+}
 
 /* COMPLETE */
 const ISOFileDef* FindISOFile(char* name) {
@@ -239,7 +313,24 @@ s32 GetISOFileLength(const ISOFileDef* fd) {
   return g_pFileSystem->GetLength(fd);
 }
 
-int NullCallback(ISO_Msg* msg) {
+int CopyDataToEE(ISO_Hdr* msg) {
+  return CopyData((ISO_LoadSingle*)msg, 0);
+}
+
+int CopyDataToIOP(ISO_Hdr* msg) {
+  return CopyData((ISO_LoadSingle*)msg, 1);
+}
+
+int CopyDataTo989snd(ISO_Hdr* msg) {
+  return CopyData((ISO_LoadSingle*)msg, 2);
+}
+
+int CopyData(ISO_LoadSingle*, int) {
+  ASSERT_NOT_REACHED();
+  return 0;
+}
+
+int NullCallback(ISO_Hdr* msg) {
   return 7;
 }
 
diff --git a/game/overlord/jak3/iso.h b/game/overlord/jak3/iso.h
index 2ddf613f7..9d7f5b69a 100644
--- a/game/overlord/jak3/iso.h
+++ b/game/overlord/jak3/iso.h
@@ -4,6 +4,15 @@
 #include "game/sce/iop.h"
 
 namespace jak3 {
+
+constexpr int LOAD_TO_EE_CMD_ID = 0x100;         // command to load file to ee
+constexpr int LOAD_TO_IOP_CMD_ID = 0x101;        // command to load to iop
+constexpr int LOAD_TO_EE_OFFSET_CMD_ID = 0x102;  // command to load file to ee with offset.
+constexpr int LOAD_TO_989SND = 0x103;
+constexpr int PAUSE_VAG_STREAM = 0x403;     // Command to pause a vag stream
+constexpr int CONTINUE_VAG_STREAM = 0x404;  // Command to continue a vag stream
+constexpr int SET_DIALOG_VOLUME = 0x406;    // Command to set the volume of vag playback
+
 extern int g_nISOMbx;
 
 struct ISO_Hdr {
@@ -22,8 +31,9 @@ struct ISO_Msg : ISO_Hdr {
   u32 msg_kind;
   int mbx_to_reply;
   int thread_id;
-  int (*callback)(ISO_Msg*);
+  int (*callback)(ISO_Hdr*);
   CBaseFile* file;
+  u32 priority;
 };
 
 struct ISO_LoadDGO : ISO_Msg {
@@ -36,6 +46,11 @@ struct ISO_LoadSingle : ISO_Msg {
   u32 length;
   u32 length_to_copy;
   u32 offset;
+  char* filename;
+  u32 unk40;
+  void* unk44;
+  u32 unk48;
+  u32 unk4c;
 };
 
 int InitISOFS(const char* fs_mode, const char* loading_sceeen);
diff --git a/game/overlord/jak3/iso_queue.cpp b/game/overlord/jak3/iso_queue.cpp
index dc457a021..92561d525 100644
--- a/game/overlord/jak3/iso_queue.cpp
+++ b/game/overlord/jak3/iso_queue.cpp
@@ -1,6 +1,10 @@
 #include "iso_queue.h"
 
+#include "common/log/log.h"
+#include "common/util/Assert.h"
+
 #include "game/overlord/jak3/pagemanager.h"
+#include "game/overlord/jak3/util.h"
 #include "game/sce/iop.h"
 
 namespace jak3 {
@@ -13,6 +17,8 @@ u32 g_auTrapSRAM[N_VAG_CMDS];
 int g_nPriQueueSema;
 int g_nISOSema;
 
+PriStackEntry gPriStack[N_PRIORITIES];
+
 CPageManager g_PageManager;
 
 void InitBuffers() {
@@ -32,4 +38,41 @@ void InitBuffers() {
   semap.option = 0;
   g_nISOSema = CreateSema(&semap);
 }
+
+bool QueueMessage(ISO_Msg* msg, int priority) {
+  msg->m_nStatus = 2;
+  msg->priority = priority;
+
+  int level = priority == 5;
+
+  {
+    ScopedLock l(g_nPriQueueSema);
+
+    if (gPriStack[level].count != 8) {
+      gPriStack[level].entries[gPriStack[level].count] = msg;
+      gPriStack[level].count++;
+
+      return true;
+    }
+  }
+
+  msg->m_nStatus = 4;
+  ReturnMessage(msg);
+
+  return false;
+}
+
+void UnqueueMessage(ISO_Msg* msg) {}
+
+void ReturnMessage(ISO_Msg* msg) {
+  if (msg->mbx_to_reply) {
+    SendMbx(msg->mbx_to_reply, msg);
+  } else if (msg->thread_id) {
+    WakeupThread(msg->thread_id);
+  } else {
+    // FreeVAGCommand(msg);
+    ASSERT_NOT_REACHED_MSG("unimplemented");
+  }
+}
+
 }  // namespace jak3
diff --git a/game/overlord/jak3/iso_queue.h b/game/overlord/jak3/iso_queue.h
index 2433d56a3..156d26571 100644
--- a/game/overlord/jak3/iso_queue.h
+++ b/game/overlord/jak3/iso_queue.h
@@ -1,8 +1,21 @@
 #ifndef ISO_QUEUE_H_
 #define ISO_QUEUE_H_
 
+#include "game/overlord/jak3/iso.h"
+
 namespace jak3 {
+constexpr int N_PRIORITIES = 2;
+constexpr int PRI_STACK_LENGTH = 8;
+
+struct PriStackEntry {
+  ISO_Msg* entries[PRI_STACK_LENGTH];
+  int count;
+};
+
 void InitBuffers();
-}
+bool QueueMessage(ISO_Msg* msg, int priority);
+void ReturnMessage(ISO_Msg* msg);
+void UnqueueMessage(ISO_Msg* msg);
+}  // namespace jak3
 
 #endif  // ISO_QUEUE_H_
diff --git a/game/overlord/jak3/pagemanager.cpp b/game/overlord/jak3/pagemanager.cpp
index 6e3384028..f4a82e9d6 100644
--- a/game/overlord/jak3/pagemanager.cpp
+++ b/game/overlord/jak3/pagemanager.cpp
@@ -155,4 +155,37 @@ int CPageManager::TryFreePages(int nPages) {
   return 0;
 }
 
+CPageManager::CPageList* CPageManager::AllocPageList(int nPages, char unk) {
+  CPageList* pList = nullptr;
+  CPage* apCollectedPages[29];
+  int nPageCount;
+
+  if (nPages <= 0) {
+    return nullptr;
+  }
+
+  if (m_Cache.m_nNumFree < nPages) {
+    if (nPages >= 29) {
+      return nullptr;
+    }
+
+    int nFreed = TryFreePages(nPages);
+    if (nFreed < nPages) {
+      return nullptr;
+    }
+  }
+
+  int nPageListID = std::countr_one(m_Cache.m_uAllocatedListMap);
+  if (nPages >= 29) {
+    return nullptr;
+  }
+
+  m_Cache.m_uAllocatedListMap |= 1u << nPageListID;
+
+  nPageCount = 0;
+  while (nPageCount < nPages) {
+    int nPageID = std::countr_one(m_Cache.m_uAllocatedPageMap);
+  }
+}
+
 }  // namespace jak3