Mystery Gift is an option on the home menu allowing you to obtain Pokémon or Avatars with special codes found on Sam's site. All of the public giveaways have been Pokémon or Avatars.
If you're looking for the Pokemon Tower Defense: Generations Mystery gift, click here.

Sam has stated that no new Mystery Gifts will be released.

How To Receive

To receive a Mystery gift, you will need a certain code; this code can be found out by solving a puzzle. Then enter "Mystery Gift" on the game menu and type or paste the code in. Then click the "Enter Code" button. Mystery Gift codes can be used more than once to receive the gift multiple times. Codes are not case sensitive.

You can also find the weekly code on the Sam & Dan Games blog. There are also periodic giveaways from Sam's twitter that you can win by answering questions. Make sure you are using the correct version of PTD to input the code, or else it won't work.

Codes

Usable

v0.8 - v1.0
Missingno: sndgames

Expired

• expire (verb): Cease to be valid, typically after a fixed period of time.
  Unless Sam unexpectedly and benevolently decides to do otherwise, the following codes will remain expired (adj: invalid) indefinitely. No comments (etc.) placed on this wiki will persuade him otherwise.

v6.5
Shadow Missingno: s20r25o4

v6.4
Mew: 340rm3n4

v6.3
Shiny Missingno: 46233nc4

v6.2
Missingno.: s40rf534

v6.1
Shadow Lickitung: 6432p562

v6.0
Aerodactyl: 43782552

v5.9
Seel: t21r2st4

v5.8
Ponyta: 65816334

v5.7
Tangela: n41r7376

v5.6
Lickitung: sac34544

v5.5
Grimer: 36657b84

v5.4
Bulbasaur Hat Avatar: 87451661

v5.3
Elf Avatar: 46233nc4

v5.2
Delibird Avatar: 36657p84

v5.0 - v5.1
Victini: 11262011

v4.9.6
Horsea: 35394175

v4.9
Alakazam Avatar: s21r25o4

v4.7 - v4.8
Gastly Avatar: 11312011

v4.6
Goldeen: 53s5n274

v4.5
Krabby: 38257p84

v4.4
Cubone Avatar: 343165b0

v4.3
Venonat: s21r25o4

v4.2
Magnemite: n41r7594

v4.0 - v4.2
Celebi Hoodie Avatar: 8b293b64

v3.8.1 - v3.9
Camper Avatar: 365a1843

v3.7
Team Rocket Avatar: 944bn284

v3.6.1
Bug Catcher Avatar: 4b1r9584

v3.5
Shiny Geodude Hat: 361rnb34

v3.3
Raikou: 361rc454

Entei: e94b6253

Suicune: gs9014z1

v3.2.1
Tentacool: 461r3t44

v3.1.5

Staryu: n31r7595

v3.1
Onix: 851r3b64

v3.0.1
Shiny Spearow: 721r6934

v2.8 - v2.9.1
Shiny Charmander: 381rm1n4

v2.7
Shiny Abra: s16928o4

v2.6
Shiny Zubat: p0k35644

v2.5
Shiny Rattata: 01543on4

v2.4
Shiny Jigglypuff: 673034

v2.3
Shiny Pidgey: 5234

Trivia

• Victini's Mystery Gift code is the only code that is identical to the date of its release (11-26-2011). It is also Sam's Birthday. However, the Gastly avatar was supposed to have 10312011 (10-31-2011), but Sam put 11312011 (11-31-2011).
  • Sam's birthday mystery gift could have been Jirachi, Shaymin, Celebi, or Victini (Version 5.0), but Victini was chosen for this gift.
• On 12/13/2011, if you had a Delibird Costume on you couldn't enter the Avatar Chat; this is because Avatar Chat needs to be updated with every new avatar.
• Tangela's mystery code was originally "114", which is its Pokedex number.
• The mystery gift will no longer change weekly; it will stay on normal Missingno untill further notice.