Pokémon XY Save File Structure

X/Y Save files are comprised of 4 sections, the latter two storing the contents of the two savegames.

The game alternates between the two game saves similar to Generations 3 & 4.

Save files are 0x100000 (1MB). The area between sections is either FF or 00, for Cartridges and Digital saves respectively.

Single Partition Save File

http://3dbrew.org/wiki/Savegames

Image Header (0x00000-0x00460)

Offset	Length	Value	Description
00000	0x10	--	AES MAC Header
00100	0x100	--	DISA
00200	0x130	--	DIFI Blob 1
00330	0x130	--	DIFI Blob 2

First Partition (0x01000-0x01107)

Save File 1 (0x02000 - 0x6AFFF)

(420 KB)

ID	Start	Length	CHK	Description
0000	05400	000002C8	6A81A	05400 - Pokepuff Inventory (Index * 100ct) 05464 - u32 counter
0001	05800	00000B88	6A822	05800 - Items Pocket 05E40 - Key Items Pocket 05FC0 - TM Pocket 06168 - Medicine Pocket 06268 - Berry Pocket
0002	06400	0000002C	6A82A	Select Bound Items
0003	06600	0000002C	6A82A	????
0004	06800	00000038	6A83A	Trainer Stat Flags (Style)
0005	06A00	00000004	6A842	????
0006	06C00	00000008	6A84A	????
0007	06E00	000001C0	6A852	Wardrobe (Bitflags) & Saved Outfits (Index #s)
0008	07000	000000BE	6A85A	u16/u8 storage
0009	07200	00000024	6A862	FFFFFFFF
000A	07400	00002100	6A86A	Overworld Data
000B	09600	00000140	6A872	Trainer Information ($)
000C	09800	00000440	6A87A	Box Names
000D	09E00	00000574	6A882	Battle Box
000E	0A400	00004E28	6A88A	PSS Data - Friends
000F	0F400	00004E28	6A892	PSS Data - Acquaintances
0010	14400	00004E28	6A89A	PSS Data - Passerby
0011	19400	00000170	6A8A2	Trainer Card (ID/SID/OT/Greeting)
0012	19600	0000061C	6A8AA	Party Members
0013	19E00	00000504	6A8B2	Constant & Event Flags
0014	1A400	000006A0	6A8BA	Pokedex
0015	1AC00	00000644	6A8C2	Sorted Variables
0016	1B400	00000104	6A8CA	Fused Zekrom/Reshiram Storage
0017	1B600	00000004	6A8D2	????
0018	1B800	00000420	6A8DA	????
0019	1BE00	00000064	6A8E2	O-Power Flags
001A	1C000	000003F0	6A8EA	????
001B	1C400	0000070C	6A8F2	User Metadata
001C	1CC00	00000180	6A8FA	GTS Upload & Match Criteria
001D	1CE00	00000004	6A902	????
001E	1D000	0000000C	6A90A	????
001F	1D200	00000048	6A912	????
0020	1D400	00000054	6A91A	????
0021	1D600	00000644	6A922	????
0022	1D800	000005C8	6A92A	Tournament Data
0023	1E400	000002F8	6A932	MAC Address & Network Connection Logging
0024	1E800	00001B40	6A93A	Hall of Fame Data (First Game Clear + 15 Latest)
0025	20400	000001F4	6A942	Maison Data
0026	20600	000001F0	6A94A	Daycare Data
0027	20800	00000216	6A952	Egg Data
0028	20C00	00000390	6A95A	Berry Field Data (0x18 per tree, 36 trees)
0029	21000	00001A90	6A962	Wondercard Data 0x100 bitflag-card received storage Wondercard slots (0x108 between)
002A	22C00	00000308	6A96A	EBUS Pokemon Storage
002B	23000	00000618	6A972	Friend Safari Data
002C	23800	0000025C	6A97A	PSS Data
002D	23C00	00000834	6A982	Medals
002E	24600	00000318	6A98A	Species related history
002F	24A00	000007D0	6A992	????
0030	25400	00000C48	6A99A	Pokemon Bank Gifts
0031	26000	00000078	6A9A2	????
0032	26200	00000200	6A9AA	PGL Promotion Gifts
0033	26400	00000C84	6A9B2	????
0034	27200	00000628	6A9BA	????
0035	27A00	00034AD0	6A9C2	Box Data (31 Boxes, 30 Slots, 232 bytes each)
0036	5C600	0000E058	6A9CA	Picture Data (JPEG Exif Ver 2.2) ~ 5C654 starts the JPEG (FF D8 marker) - Sent to PGL
----	6A800	00000800	-----	Checksum Storage [0x14] Header: u64 savetime1 & u64 savetime2, u16 BEEF magic [0x10] Checksum Entries: u32 len, u16 ID, u16 checksum (ccitt16, 0xFFFF initial)

Save File 2 (0x81000 - 0xE9FFF)