diff --git a/mission/system/tree/acsModeTree.cpp b/mission/system/tree/acsModeTree.cpp
index 0474d0a1..55b4ac70 100644
--- a/mission/system/tree/acsModeTree.cpp
+++ b/mission/system/tree/acsModeTree.cpp
@@ -94,7 +94,7 @@ auto ACS_TABLE_PTG_TARGET_INERTIAL_TGT =
 auto ACS_TABLE_PTG_TARGET_INERTIAL_TRANS_1 =
     std::make_pair((acs::AcsMode::PTG_INERTIAL << 24) | 3, FixedArrayList<ModeListEntry, 1>());
 
-void satsystem::acs::init() {
+Subsystem& satsystem::acs::init() {
   ModeListEntry entry;
   const char* ctxc = "satsystem::acs::init: generic target";
   // Insert Helper Table
@@ -123,6 +123,7 @@ void satsystem::acs::init() {
   buildTargetPtNadirSequence(ACS_SUBSYSTEM, entry);
   buildTargetPtInertialSequence(ACS_SUBSYSTEM, entry);
   ACS_SUBSYSTEM.setInitialMode(::acs::AcsMode::SAFE);
+  return ACS_SUBSYSTEM;
 }
 
 namespace {
diff --git a/mission/system/tree/acsModeTree.h b/mission/system/tree/acsModeTree.h
index 134a86a7..27236fba 100644
--- a/mission/system/tree/acsModeTree.h
+++ b/mission/system/tree/acsModeTree.h
@@ -4,7 +4,7 @@ namespace satsystem {
 namespace acs {
 
 extern AcsSubsystem ACS_SUBSYSTEM;
-void init();
+Subsystem& init();
 
 }  // namespace acs
 }  // namespace satsystem
diff --git a/mission/system/tree/comModeTree.cpp b/mission/system/tree/comModeTree.cpp
index e08ba5ba..4474cc62 100644
--- a/mission/system/tree/comModeTree.cpp
+++ b/mission/system/tree/comModeTree.cpp
@@ -62,13 +62,14 @@ void buildTxAndRxDefaultRateSequence(Subsystem& ss, ModeListEntry& eh);
 
 }  // namespace
 
-void satsystem::com::init() {
+Subsystem& satsystem::com::init() {
   ModeListEntry entry;
   buildRxOnlySequence(SUBSYSTEM, entry);
   buildTxAndRxLowRateSequence(SUBSYSTEM, entry);
   buildTxAndRxHighRateSequence(SUBSYSTEM, entry);
   buildTxAndRxDefaultRateSequence(SUBSYSTEM, entry);
   SUBSYSTEM.setInitialMode(NML, ::com::Submode::RX_ONLY);
+  return SUBSYSTEM;
 }
 
 namespace {
diff --git a/mission/system/tree/comModeTree.h b/mission/system/tree/comModeTree.h
index ccc7f15f..f4648598 100644
--- a/mission/system/tree/comModeTree.h
+++ b/mission/system/tree/comModeTree.h
@@ -8,7 +8,7 @@ namespace satsystem {
 namespace com {
 extern ComSubsystem SUBSYSTEM;
 
-void init();
+Subsystem& init();
 }  // namespace com
 
 }  // namespace satsystem
diff --git a/mission/system/tree/payloadModeTree.cpp b/mission/system/tree/payloadModeTree.cpp
index ccb3dd2c..5262c61e 100644
--- a/mission/system/tree/payloadModeTree.cpp
+++ b/mission/system/tree/payloadModeTree.cpp
@@ -20,7 +20,7 @@ void initEarthObsvSequence(Subsystem& ss, ModeListEntry& eh);
 void initScexSequence(Subsystem& ss, ModeListEntry& eh);
 }  // namespace
 
-Subsystem satsystem::pl::SUBSYSTEM = Subsystem(objects::PL_SUBSYSTEM, 12, 24);
+PayloadSubsystem satsystem::pl::SUBSYSTEM = PayloadSubsystem(objects::PL_SUBSYSTEM, 12, 24);
 
 const auto check = subsystem::checkInsert;
 static const auto OFF = HasModesIF::MODE_OFF;
@@ -77,7 +77,7 @@ auto PL_TABLE_SCEX_TGT =
 auto PL_TABLE_SCEX_TRANS_0 =
     std::make_pair((payload::Mode::SCEX << 24) | 2, FixedArrayList<ModeListEntry, 1>());
 
-void satsystem::pl::init() {
+Subsystem& satsystem::pl::init() {
   ModeListEntry entry;
   initOffSequence(SUBSYSTEM, entry);
   initPlMpsocStreamSequence(SUBSYSTEM, entry);
@@ -86,6 +86,7 @@ void satsystem::pl::init() {
   initEarthObsvSequence(SUBSYSTEM, entry);
   initScexSequence(SUBSYSTEM, entry);
   SUBSYSTEM.setInitialMode(OFF);
+  return SUBSYSTEM;
 }
 
 namespace {
diff --git a/mission/system/tree/payloadModeTree.h b/mission/system/tree/payloadModeTree.h
index d1eae4d7..55cd6991 100644
--- a/mission/system/tree/payloadModeTree.h
+++ b/mission/system/tree/payloadModeTree.h
@@ -1,15 +1,15 @@
 #ifndef MISSION_SYSTEM_TREE_PAYLOADMODETREE_H_
 #define MISSION_SYSTEM_TREE_PAYLOADMODETREE_H_
 
-#include <fsfw/subsystem/Subsystem.h>
+#include <mission/system/objects/PayloadSubsystem.h>
 
 namespace satsystem {
 
 namespace pl {
 
-extern Subsystem SUBSYSTEM;
+extern PayloadSubsystem SUBSYSTEM;
 
-void init();
+Subsystem& init();
 }  // namespace pl
 
 }  // namespace satsystem
diff --git a/mission/system/tree/system.cpp b/mission/system/tree/system.cpp
index bf6cea9d..b176efe6 100644
--- a/mission/system/tree/system.cpp
+++ b/mission/system/tree/system.cpp
@@ -1,13 +1,99 @@
 #include "system.h"
 
+#include <fsfw/devicehandlers/DeviceHandlerIF.h>
+#include <fsfw/subsystem/Subsystem.h>
+#include <mission/acsDefs.h>
+
 #include "acsModeTree.h"
 #include "comModeTree.h"
+#include "eive/objects.h"
 #include "payloadModeTree.h"
 #include "tcsModeTree.h"
+#include "util.h"
+
+namespace {
+// Alias for checker function
+const auto check = subsystem::checkInsert;
+
+void buildSafeSequence(Subsystem& ss, ModeListEntry& eh);
+}  // namespace
+
+static const auto OFF = HasModesIF::MODE_OFF;
+static const auto NML = DeviceHandlerIF::MODE_NORMAL;
 
 void satsystem::init() {
-  acs::init();
-  pl::init();
-  tcs::init();
-  com::init();
+  auto& acsSubsystem = acs::init();
+  acsSubsystem.connectModeTreeParent(EIVE_SYSTEM);
+  auto& payloadSubsystem = pl::init();
+  payloadSubsystem.connectModeTreeParent(EIVE_SYSTEM);
+  auto& tcsSubsystem = tcs::init();
+  tcsSubsystem.connectModeTreeParent(EIVE_SYSTEM);
+  auto& comSubsystem = com::init();
+  comSubsystem.connectModeTreeParent(EIVE_SYSTEM);
+  ModeListEntry entry;
+  buildSafeSequence(EIVE_SYSTEM, entry);
 }
+
+EiveSystem satsystem::EIVE_SYSTEM = EiveSystem(objects::EIVE_SYSTEM, 12, 24);
+
+auto EIVE_SEQUENCE_SAFE = std::make_pair(acs::AcsMode::SAFE, FixedArrayList<ModeListEntry, 5>());
+auto EIVE_TABLE_SAFE_TGT =
+    std::make_pair((acs::AcsMode::SAFE << 24) | 1, FixedArrayList<ModeListEntry, 5>());
+auto EIVE_TABLE_SAFE_TRANS_0 =
+    std::make_pair((acs::AcsMode::SAFE << 24) | 2, FixedArrayList<ModeListEntry, 5>());
+auto EIVE_TABLE_SAFE_TRANS_1 =
+    std::make_pair((acs::AcsMode::SAFE << 24) | 3, FixedArrayList<ModeListEntry, 5>());
+
+auto EIVE_SEQUENCE_IDLE =
+    std::make_pair(acs::AcsMode::PTG_IDLE, FixedArrayList<ModeListEntry, 5>());
+auto EIVE_TABLE_IDLE_TGT =
+    std::make_pair((acs::AcsMode::PTG_IDLE << 24) | 1, FixedArrayList<ModeListEntry, 5>());
+auto EIVE_TABLE_IDLE_TRANS_0 =
+    std::make_pair((acs::AcsMode::PTG_IDLE << 24) | 2, FixedArrayList<ModeListEntry, 5>());
+
+namespace {
+
+void buildSafeSequence(Subsystem& ss, ModeListEntry& eh) {
+  std::string context = "satsystem::buildSafeSequence";
+  auto ctxc = context.c_str();
+  // Insert Helper Table
+  auto iht = [&](object_id_t obj, Mode_t mode, Submode_t submode, ArrayList<ModeListEntry>& table) {
+    eh.setObject(obj);
+    eh.setMode(mode);
+    eh.setSubmode(submode);
+    check(table.insert(eh), ctxc);
+  };
+  // Insert Helper Sequence
+  auto ihs = [&](ArrayList<ModeListEntry>& sequence, Mode_t tableId, uint32_t waitSeconds,
+                 bool checkSuccess) {
+    eh.setTableId(tableId);
+    eh.setWaitSeconds(waitSeconds);
+    eh.setCheckSuccess(checkSuccess);
+    check(sequence.insert(eh), ctxc);
+  };
+
+  // Only tracks that payload is off
+  iht(objects::PL_SUBSYSTEM, OFF, 0, EIVE_TABLE_SAFE_TGT.second);
+  check(ss.addTable(TableEntry(EIVE_TABLE_IDLE_TGT.first, &EIVE_TABLE_IDLE_TGT.second)), ctxc);
+
+  // Build SAFE transition 0
+  iht(objects::TCS_SUBSYSTEM, NML, 0, EIVE_TABLE_SAFE_TRANS_0.second);
+  check(ss.addTable(TableEntry(EIVE_TABLE_SAFE_TRANS_0.first, &EIVE_TABLE_SAFE_TRANS_0.second)),
+        ctxc);
+
+  // Build SAFE transition 1
+  iht(objects::PL_SUBSYSTEM, OFF, 0, EIVE_TABLE_SAFE_TRANS_1.second);
+  iht(objects::ACS_SUBSYSTEM, acs::AcsMode::SAFE, 0, EIVE_TABLE_SAFE_TRANS_1.second);
+  check(ss.addTable(TableEntry(EIVE_TABLE_SAFE_TRANS_1.first, &EIVE_TABLE_SAFE_TRANS_1.second)),
+        ctxc);
+
+  // Build Safe sequence
+  ihs(EIVE_SEQUENCE_SAFE.second, EIVE_TABLE_SAFE_TGT.first, 0, false);
+  ihs(EIVE_SEQUENCE_SAFE.second, EIVE_TABLE_SAFE_TRANS_0.first, 0, false);
+  ihs(EIVE_SEQUENCE_SAFE.second, EIVE_TABLE_SAFE_TRANS_1.first, 2, false);
+  check(ss.addSequence(SequenceEntry(EIVE_SEQUENCE_SAFE.first, &EIVE_SEQUENCE_SAFE.second,
+                                     EIVE_SEQUENCE_SAFE.first)),
+        ctxc);
+}
+
+}  // namespace
diff --git a/mission/system/tree/system.h b/mission/system/tree/system.h
index a8599121..b1c90c82 100644
--- a/mission/system/tree/system.h
+++ b/mission/system/tree/system.h
@@ -1,10 +1,14 @@
 #ifndef MISSION_SYSTEM_TREE_SYSTEM_H_
 #define MISSION_SYSTEM_TREE_SYSTEM_H_
 
+#include <mission/system/objects/EiveSystem.h>
+
 namespace satsystem {
 
 void init();
 
-}
+extern EiveSystem EIVE_SYSTEM;
+
+}  // namespace satsystem
 
 #endif /* MISSION_SYSTEM_TREE_SYSTEM_H_ */
diff --git a/mission/system/tree/tcsModeTree.cpp b/mission/system/tree/tcsModeTree.cpp
index 51b0ec79..96b936bf 100644
--- a/mission/system/tree/tcsModeTree.cpp
+++ b/mission/system/tree/tcsModeTree.cpp
@@ -27,11 +27,12 @@ auto TCS_TABLE_NORMAL_TGT = std::make_pair((NML << 24) | 1, FixedArrayList<ModeL
 auto TCS_TABLE_NORMAL_TRANS_0 = std::make_pair((NML << 24) | 2, FixedArrayList<ModeListEntry, 7>());
 auto TCS_TABLE_NORMAL_TRANS_1 = std::make_pair((NML << 24) | 3, FixedArrayList<ModeListEntry, 2>());
 
-void satsystem::tcs::init() {
+Subsystem& satsystem::tcs::init() {
   ModeListEntry entry;
   buildOffSequence(SUBSYSTEM, entry);
   buildNormalSequence(SUBSYSTEM, entry);
   SUBSYSTEM.setInitialMode(OFF);
+  return SUBSYSTEM;
 }
 
 namespace {
diff --git a/mission/system/tree/tcsModeTree.h b/mission/system/tree/tcsModeTree.h
index 33fe7701..af10e60b 100644
--- a/mission/system/tree/tcsModeTree.h
+++ b/mission/system/tree/tcsModeTree.h
@@ -6,7 +6,7 @@ namespace satsystem {
 namespace tcs {
 
 extern Subsystem SUBSYSTEM;
-void init();
+Subsystem& init();
 
 }  // namespace tcs
 }  // namespace satsystem
diff --git a/tmtc b/tmtc
index 8d23f29f..6db34aac 160000
--- a/tmtc
+++ b/tmtc
@@ -1 +1 @@
-Subproject commit 8d23f29f947e2a4f79e1fc0910cd9ad59a4fc346
+Subproject commit 6db34aacaabedf69f05b330d71e25cc7cedb5632