diff --git a/src/AI/zappy_ia/DecisionTree.py b/src/AI/zappy_ia/DecisionTree.py
index 47a35b50..f7f0486d 100644
--- a/src/AI/zappy_ia/DecisionTree.py
+++ b/src/AI/zappy_ia/DecisionTree.py
@@ -109,14 +109,12 @@ def inventory(self):
         try:
             rescpy = res
             res = res.split("[")[1].split("]")[0]
-        except IndexError:
+            for elem in res.split(","):
+                parsedElem = elem.strip().split(" ")
+                self._inputTree["m" + parsedElem[0]][0] = int(parsedElem[1])
+        except (IndexError, ValueError) as error:
             print(f"ID : {self._clientManager._id} crashed in inventory when received : ", rescpy)
             self._clientManager.stopClient()
-            return
-
-        for elem in res.split(","):
-            parsedElem = elem.strip().split(" ")
-            self._inputTree["m" + parsedElem[0]][0] = int(parsedElem[1])
 
     def lookForTree(self):
         """
@@ -300,10 +298,13 @@ def elevation(self):
                 )
         res = self._clientManager.requestClient(Command.INCANTATION)
         if (res == "ko\n"):
+            self._clientManager.requestClient(Command.FORWARD)
             return
         out = self._clientManager.waitOutput()
         if out != Message.KO.value + "\n":
             self.incrementLevel()
+        else:
+            self._clientManager.requestClient(Command.FORWARD)
 
     def takeClosestFood(self):
         self.look()
@@ -363,12 +364,13 @@ def elevationEmitter(self):
         This function is call by decision tree when the ia have the stones for elevation,
             the ia call others to try elevation
         """
-        self._clientManager.sendBroadcast(list(Message)[self._level].value)
         participantsId: List[int] = []
         res: List[Tuple[int, str, List[int], int]] = []
-        time.sleep(1)
-        res = self._clientManager.checkBroadcastWithoutNewElevation()
-        for mess in res:
-            participantsId = self.checkReceivedMessage(participantsId, mess)
-        if len(participantsId) == levelParticipantsNb[self._level]:
-            self.waitParticipants(participantsId)
+        while len(participantsId) < levelParticipantsNb[self._level]:
+            self._clientManager.sendBroadcast(list(Message)[self._level].value)
+            res = self._clientManager.checkBroadcastWithoutNewElevation()
+            for mess in res:
+                participantsId = self.checkReceivedMessage(participantsId, mess)
+            self.takeClosestFood()
+        self._clientManager.sendBroadcast(Message.OK.value, participantsId)
+        self.waitParticipants(participantsId)
diff --git a/src/AI/zappy_ia/ElevationParticipant.py b/src/AI/zappy_ia/ElevationParticipant.py
index 5bd09d16..10c8427a 100644
--- a/src/AI/zappy_ia/ElevationParticipant.py
+++ b/src/AI/zappy_ia/ElevationParticipant.py
@@ -53,11 +53,38 @@ def joinEmitter(self):
         else:
             return self.errorReturn()
 
+    def checkBroadcastEmitter(self) -> List[Tuple[int, str, List[int], int]]:
+        broadcasts = self._clientManager.checkBroadcast()
+        res: List[Tuple[int, str, List[int], int]] = []
+        for mess in broadcasts:
+            if mess[2][0] == 0:
+                if mess[0] == self._emitter:
+                    continue
+                else:
+                    self._clientManager.sendBroadcast(Message.KO.value, [mess[0]])
+            elif mess[0] == self._emitter:
+                res.append(mess)
+            else:
+                self._log.debug("weird message in check broadcast emitter: " + mess[1])
+        return res
+
+    def waitNextStep(self) -> bool:
+        okNb = 0
+        res: Tuple[int, str, List[int], int] = [0, "", [], 0]
+        while okNb < 2:
+            res = self.checkBroadcastEmitter()
+            for mess in res:
+                if mess[1] == Message.KO.value:
+                    return False
+                elif mess[1] == Message.OK.value:
+                    okNb += 1
+                else:
+                    self._log.debug("weird message in wait next step: " + mess[1])
+            self._decisionTree.takeClosestFood()
+        return True
+
     def elevationParticipant(self) -> bool:
-        res = self._clientManager.checkBroadcastResponse()
-        while res[1] == "":
-            res = self._clientManager.checkBroadcastResponse()
-        if res[1] == Message.KO.value:
+        if self.waitNextStep() == False:
             return self.errorReturn()
         haveToCome = False
         ready = False
diff --git a/src/SERVER/src/trantorien/commands/command_incantation.c b/src/SERVER/src/trantorien/commands/command_incantation.c
index e972d4f8..5bb03c64 100644
--- a/src/SERVER/src/trantorien/commands/command_incantation.c
+++ b/src/SERVER/src/trantorien/commands/command_incantation.c
@@ -15,7 +15,10 @@
 #include "client.h"
 #include "command_reponses.h"
 
-static const char *format_error_level = "Incantation: too many/less "
+static const char *format_error_too_many_level = "Incantation: too many"
+                                        "trantoriens at level %d\n";
+
+static const char *format_error_too_less_level = "Incantation: too less "
                                         "trantoriens at level %d\n";
 
 static const char *format_error_resource = "Incantation: too less "
@@ -56,6 +59,11 @@ static bool check_incantation_lvl_availability(trantorien_t *ref_trnt,
             nb_trantorien_lvl += 1;
         }
     }
+    if (nb_trantorien_lvl < nb_level_players[trantorien_lvl - 1]) {
+        fprintf(stderr, format_error_too_less_level, trantorien_lvl);
+    } else if (nb_trantorien_lvl > nb_level_players[trantorien_lvl - 1]) {
+        fprintf(stderr, format_error_too_many_level, trantorien_lvl);
+    }
     return (nb_trantorien_lvl == nb_level_players[trantorien_lvl - 1]);
 }
 
@@ -78,7 +86,6 @@ bool check_incantation_availability(trantorien_t *trantorien, map_t *map,
         }
     }
     if (check_incantation_lvl_availability(trantorien, ntw) == false) {
-        fprintf(stderr, format_error_level, trantorien->level);
         return false;
     }
     return true;