Groundwork

Letter is there, post-game warp is done, new post-game event where you receive the letter isn't working properly

engine/debug/debug_party.asm

@@ -187,9 +187,9 @@ DebugPikachuEevee:
 	jr .loop
 
 DebugPikachuEeveeShows:
-		db HS_DAMIEN ; Charmander guy
-		db HS_VERMILION_JENNY ; Squirtle
-		db -1 ; end
+	db HS_DAMIEN ; Charmander guy
+	db HS_VERMILION_JENNY ; Squirtle
+	db -1 ; end
 
 DebugSetPokedexEntries:
 	ld b, wPokedexOwnedEnd - wPokedexOwned
@@ -203,6 +203,7 @@ DebugSetPokedexEntries:
 
 DebugItemsList:
 	db MASTER_BALL, 99
+	db SILPHLETTER, 1
 	db MYSTERY_BOX, 1
 	db CANDY_JAR, 1
 	db BICYCLE, 1

engine/items/item_effects.asm

@@ -111,6 +111,7 @@ ItemUsePtrTable:
 	dw ItemUseEvoStone   ; METAL_COAT
 	dw ItemUseMysteryBox ; MYSTERY_BOX
 	dw UnusableItem		 ; TEA
+	dw ItemUseLetter	 ; SILPHLETTER
 	dw UnusableItem      ; FLOOR_B2F
 	dw UnusableItem      ; FLOOR_B1F
     dw UnusableItem      ; FLOOR_1F
@@ -126,6 +127,16 @@ ItemUsePtrTable:
 	dw UnusableItem      ; FLOOR_11F
 	dw UnusableItem      ; FLOOR_14F
 
+ItemUseLetter:
+	text_asm
+	ld hl, ChiefLetterText
+	call PrintText
+	jp TextScriptEnd
+
+ChiefLetterText:
+	text_far _ChiefLetterText
+	text_end
+
 ItemUseMysteryBox:
 	; Mystery Box can't be used in battle.
 	ld a, [wIsInBattle]

engine/menus/item_descriptions.asm

@@ -202,6 +202,8 @@ ItemDescriptionPointers:
 	text_end
 	text_far _TeaDescription
 	text_end
+	text_far _SilphLetterDescription
+	text_end
 	text_far _HM01Description
 	text_end
 	text_far _HM02Description

engine/menus/main_menu.asm

@@ -117,7 +117,7 @@ MainMenu:
 	ld a, [wCurMap] ; map ID
 	cp HALL_OF_FAME
 	jp nz, SpecialEnterMap
-	xor a
+	ld a, REDS_HOUSE_2F
 	ld [wDestinationMap], a
 	ld hl, wd732
 	set 2, [hl] ; fly warp or dungeon warp