diff --git a/constants/item_data_constants.asm b/constants/item_data_constants.asm
index 4f466d41..bd347153 100644
--- a/constants/item_data_constants.asm
+++ b/constants/item_data_constants.asm
@@ -58,6 +58,14 @@ DEF MAIL_MSG_LENGTH    EQU $20
 DEF MAILBOX_CAPACITY   EQU 10
 DEF MAIL_STRUCT_LENGTH EQU $2f ; mailmsg struct
 
+; mail languages
+	const_def
+	const MAIL_LANG_ENGLISH
+	const MAIL_LANG_FRENCH
+	const MAIL_LANG_GERMAN
+	const MAIL_LANG_ITALIAN
+	const MAIL_LANG_SPANISH
+
 ; held item effects
 	const_def
 	const HELD_NONE
diff --git a/constants/serial_constants.asm b/constants/serial_constants.asm
index 01ac3761..211f3d7e 100644
--- a/constants/serial_constants.asm
+++ b/constants/serial_constants.asm
@@ -29,15 +29,16 @@ DEF SERIAL_PATCH_LIST_PART_TERMINATOR EQU $ff
 ; used to replace SERIAL_NO_DATA_BYTE
 DEF SERIAL_PATCH_REPLACEMENT_BYTE     EQU $ff
 
-DEF SERIAL_PREAMBLE_LENGTH       EQU 6
-DEF SERIAL_RN_PREAMBLE_LENGTH    EQU 7
-DEF SERIAL_RNS_LENGTH            EQU 10
+DEF SERIAL_PREAMBLE_LENGTH    EQU 6
+DEF SERIAL_RN_PREAMBLE_LENGTH EQU 7
+DEF SERIAL_RNS_LENGTH         EQU 10
 
 DEF SERIAL_MAIL_PREAMBLE_BYTE    EQU $20
-DEF SERIAL_MAIL_REPLACEMENT_BYTE EQU $21
 DEF SERIAL_MAIL_PREAMBLE_LENGTH  EQU 5
+; used to replace SERIAL_NO_DATA_BYTE
+DEF SERIAL_MAIL_REPLACEMENT_BYTE EQU $21
 
 ; timeout duration after exchanging a byte
-DEF SERIAL_LINK_BYTE_TIMEOUT     EQU $5000
+DEF SERIAL_LINK_BYTE_TIMEOUT EQU $5000
 
-DEF MAX_MYSTERY_GIFT_PARTNERS    EQU 5
+DEF MAX_MYSTERY_GIFT_PARTNERS EQU 5
diff --git a/engine/link/link.asm b/engine/link/link.asm
index 856d6aa5..711c0dfa 100644
--- a/engine/link/link.asm
+++ b/engine/link/link.asm
@@ -386,7 +386,7 @@ endc
 	jr nz, .copy_mail_loop
 	ld de, wLinkReceivedMail
 	ld b, PARTY_LENGTH
-.fix_mail_loop
+.copy_author_loop
 	push bc
 	ld a, LOW(MAIL_MSG_LENGTH + 1)
 	add e
@@ -398,7 +398,7 @@ endc
 	call CopyBytes
 	pop bc
 	dec b
-	jr nz, .fix_mail_loop
+	jr nz, .copy_author_loop
 	ld de, wLinkReceivedMailEnd
 	xor a
 	ld [de], a
@@ -834,7 +834,7 @@ Link_PrepPartyData_Gen2:
 	ret nz
 
 ; Fill 5 bytes at wLinkPlayerMailPreamble with $20
-	ld de, wLinkPlayerMailPreamble
+	ld de, wLinkPlayerMail
 	ld a, SERIAL_MAIL_PREAMBLE_BYTE
 	call Link_CopyMailPreamble
 
@@ -852,6 +852,7 @@ Link_PrepPartyData_Gen2:
 	pop bc
 	dec b
 	jr nz, .loop2
+
 ; Copy the mail data to wLinkPlayerMailMetadata
 	ld hl, sPartyMail
 	ld b, PARTY_LENGTH
@@ -866,6 +867,7 @@ Link_PrepPartyData_Gen2:
 	jr nz, .loop3
 	call CloseSRAM
 
+; The SERIAL_NO_DATA_BYTE value isn't allowed anywhere in message text
 	ld hl, wLinkPlayerMailMessages
 	ld bc, (MAIL_MSG_LENGTH + 1) * PARTY_LENGTH
 .loop4
@@ -880,6 +882,7 @@ Link_PrepPartyData_Gen2:
 	or c
 	jr nz, .loop4
 
+; Calculate the patch offsets for the mail metadata
 	ld hl, wLinkPlayerMailMetadata
 	ld de, wLinkPlayerMailPatchSet
 	ld b, (MAIL_STRUCT_LENGTH - (MAIL_MSG_LENGTH + 1)) * PARTY_LENGTH