diff --git a/src/client_darc.py b/src/client_darc.py
index 6f5452d..86ec281 100644
--- a/src/client_darc.py
+++ b/src/client_darc.py
@@ -189,8 +189,8 @@ def merge_message(
     height = len(alphabet_phase3.matrix)
     width = len(alphabet_phase3.matrix[0])
     msg_len = len(input_sequence)
-    eof_arr = AlphabetKey.init_matrix(width, height, 255).matrix[0]
-    #eof_msg_mask = Mask.init_matrix(width, height, msg_len)
+
+    eof_msg_mask = Mask.init_matrix(width, height, msg_len)
 
     if msg_len < height:
         padded_input_sequence = OuterKey.init_matrix(height)
@@ -201,10 +201,6 @@ def merge_message(
     cdo1 = client_keys.persistent.data.outer_key_1 << client_keys.ephemeral.data.outer_key_1
     cdo2 = client_keys.persistent.data.outer_key_2 << client_keys.ephemeral.data.outer_key_2
 
-    alpha_ncdo1_ncdo2_inp = (alphabet_phase3 < (~(cdo1 << cdo2) << padded_input_sequence))
-    if msg_len < height:
-        alpha_ncdo1_ncdo2_inp.matrix[msg_len] = eof_arr
-
     mmi3 = mutual_keys.persistent.medium.inner_key_3 << mutual_keys.ephemeral.medium.inner_key_3
     mmi4 = mutual_keys.persistent.medium.inner_key_4 << mutual_keys.ephemeral.medium.inner_key_4
     mmo4 = mutual_keys.persistent.medium.outer_key_4 << mutual_keys.ephemeral.medium.outer_key_4
@@ -217,7 +213,7 @@ def merge_message(
     darc_message = (
                            (
                                    (medium_phase3 < ~(cmo1 << cmo2)) ^
-                                   (alpha_ncdo1_ncdo2_inp << (mmi3 < ~(mmo4 << mmo6)))
+                                   (((alphabet_phase3 < (~(cdo1 << cdo2) << padded_input_sequence)) ^ eof_msg_mask) << (mmi3 < ~(mmo4 << mmo6)))
                            ) < mmo4
                    ) << (mmi4 < (mmo5 << ~mmo6))
     return darc_message