theSLAYER

From the period of July 25th to Aug 09th, there was a Global Mission for players globally to win the lotto 1,000 times.
When the mission succeeds, players will receive 2,000 FC.
If the player draws one lotto (doesn't have to be a win), with an account Game Synced with PGL, they will get 5 Rare Candies.
Furthermore, if there is a total of 4,000 times the lotto was won, a Fast Ball will come bundled with the 5 Rare Candies.
The final count for the mission was 30,256 wins.
 
WC 1623: Un regalo de Pokémon Global Link Rare Candy
        x 5 0x38 This is a gift from the Pokémon Global Link! Please pick up your gift from the deliveryman in any Pokémon Center.
    Fast Ball                     Serial Code  |  Aug 15 to Sep 30, 2017  |  US & EU 3DS: SM Un regalo de Pokémon Global Link Gracias por participar en el minijuego global.

The 3DS app Pokémon Bank accumulates Poké Miles over the duration of time that a Pokémon is stored on the Bank itself.
The player can choose to send Poké Miles or Battle Points to a chosen Gen VI or Gen VII game.

Since Gen VII games do not use Poké Miles, players are only able to send Battle Points to the selected games,
with the conversion rate of 1 Battle Point for every 10 Poké Miles.

While the card upload only has 10 Battle Points, it is possible to receive other amounts from Pokémon Bank.

WC 1022: 더블 팩 구입 특별 선물 Potion
        x 100 0x35 Thank you for receiving this distribution! Please pick up your gift from the delivery girl in any Pokémon Center.
                          Serial Code  |  Dec 12, 2014 to Nov 30, 2015  |  KO 3DS: ORAS 더블 팩 구입 특별 선물 사용하면 포켓몬의 HP를
20 회복하는
상처약을 100개 선물!

WC 1057: 포켓몬 OR・AS 패키지 구입 특별 선물 Quick Ball
        x 50 0x36 Please pick up your gift from the delivery girl in any Pokémon Center.
                          Serial Code  |  21 April 2016 to 31 March 2017   |  KO 3DS: ORAS 포켓몬 OR・AS 패키지 구입 특별 선물 배틀이 시작되자마자
사용하면 포켓몬을 잡기 쉬워지는
퀵볼을 50개 선물!

WC 1511: TRICK OR TREAT!? Rare Candy
        x 10 0x37 This is a gift from the Pokémon Global Link! Please pick up your gift from the delivery girl in any Pokémon Center.
                          Serial Code  |  Nov 02 to Dec 16, 2015  |  KO 3DS: ORAS TRICK OR TREAT!? 인터넷 대회 「TRICK OR TREAT!?」에
무서운 이미지의 포켓몬으로
참가한 보상으로 이상한사탕을
10개 선물합니다!

WC 2048: 「무한티켓」을 선물 Eon Ticket
        x 1 0x2B Thank you for playing Pokémon! Please pick up your gift from the delivery girl in any Pokémon Center.
                          Serial Code  |  Dec 14, 2014 to May 31, 2015  |  KO 3DS: ORAS 「무한티켓」을 선물 「무한티켓」을 사용하여 갈 수 있는
「남쪽의 외딴섬」에 방문하여
「포켓몬스터 오메가루비」에서는 라티아스,
「포켓몬스터 알파사파이어」에서는 라티오스를 만나보자!

This event was distributed to players who purchased Pokemon X & Y at 7 Eleven stores and Daewon Stores,
in South Korea.
 
WC 1002: 퀵볼 선물 이벤트 Quick Ball
        x 12 0x35 Thank you for receiving this distribution! Please pick up your gift from the delivery girl in any Pokémon Center.                         Serial Code  |  Dec 01, 2013 to Feb 28, 2014  |  KO 3DS: XY 퀵볼 선물 이벤트 다운로드해 주셔서
감사합니다!
소포는 포켓몬센터에 있는
배달원에게 받으십시오!

100x Quick Balls distributed via Serial code, for purchasing the Dual Pack Retail Copies of Pokemon Sun and Pokemon Moon.
Event was Available to US, KO, JP and TW (via EU/JP 3DSes)
Distribution Title 더블 팩 구입 특전 Wondercard ID 1603     Games SM Type Serial Code Distribution Date Nov 18, 2016 to Nov 30, 2017 Item Poke Ball Quantity x100 Receiving Text 0x2C Thank you for playing Pokémon! Please pick up your gift from the deliveryman in any Pokémon Center. Distribution Text
야생 포켓몬에게 던져서 잡는 몬스터볼을
100개 선물합니다!
이 볼로 많은 포켓몬을 잡아보자!  

This wonder card is sent from the Demo to your main Pokemon Sun or Pokemon Moon game.
Distribution Title 특별체험판 혜성조각 Wondercard ID 2045 Games SM Type Demo Distribution Date No end date (simply transfer from demo) Item Comet Shard Quantity x1 Receiving Text 0x5B Thank you for playing the demo version! Please pick up your gift from the deliveryman in any Pokémon Center.

This wonder card is sent from the Demo to your main Pokemon Sun or Pokemon Moon game.
Distribution Title 특별체험판 향기버섯 Wondercard ID 2044 Games SM Type Demo Distribution Date No end date (simply transfer from demo) Item Balm Mushroom Quantity x1 Receiving Text 0x5B Thank you for playing the demo version! Please pick up your gift from the deliveryman in any Pokémon Center.

This wonder card is sent from the Demo to your main Pokemon Sun or Pokemon Moon game.
Distribution Title 특별체험판 고운날개 Wondercard ID 2043 Games SM Type Demo Distribution Date No end date (simply transfer from demo) Item Pretty Wing Quantity x10 Receiving Text 0x5B Thank you for playing the demo version! Please pick up your gift from the deliveryman in any Pokémon Center.

This wonder card is sent from the Demo to your main Pokemon Sun or Pokemon Moon game.
Distribution Title 특별체험판 금구슬 Wondercard ID 2042 Games SM Type Demo Distribution Date No end date (simply transfer from demo) Item Nugget Quantity x1 Receiving Text 0x5B Thank you for playing the demo version! Please pick up your gift from the deliveryman in any Pokémon Center.

This wonder card is sent from the Demo to your main Pokemon Sun or Pokemon Moon game.
Distribution Title 특별체험판 별의조각 Wondercard ID 2041 Games SM Type Demo Distribution Date No end date (simply transfer from demo) Item Star Piece Quantity x1 Receiving Text 0x5B Thank you for playing the demo version! Please pick up your gift from the deliveryman in any Pokémon Center.

This wonder card is sent from the Demo to your main Pokemon Sun or Pokemon Moon game.
Distribution Title 특별체험판 별의조각 Wondercard ID 2041 Games SM Type Demo Distribution Date No end date (simply transfer from demo) Item Star Piece Quantity x1 Receiving Text 0x5B Thank you for playing the demo version! Please pick up your gift from the deliveryman in any Pokémon Center.

From the period of January 31st to February 13th, there was a Global Mission to trade 1,000,000 Pokemon through the GTS.
When the mission succeeds, players will receive 2,000 FC.
If the player trades 5 times, with an account Game Synced with PGL, they will get 5 Rare Candies.
Furthermore, if 2,000,000 Pokemon was traded, a Friend ball will come bundled with the 5 Rare Candies.

The final count for the mission was 4,107,702 Pokemon traded.
Distribution Title 포켓몬 글로벌 링크 Wondercard ID 1604     Games SM Type Serial Code Distribution Date Feb 21 - Mar 31, 2017 Item Rare Candy Quantity x5 Bundled with Friend Ball x1 Receiving Text 0x38 This is a gift from the Pokémon Global Link! Please pick up your gift from the deliveryman in any Pokémon Center. Distribution Text
글로벌 어트랙션 참가 기념 선물입니다!

This event was given away using a common password M2DESCENT for all regions.
This is the first time that these Mega Stones are obtainable for Pokemon Sun & Moon.
 
WC 1605: 메가스톤 선물 Mewtwonite X
        x 1 0x2C Thank you for playing Pokémon! Please pick up your gift from the deliveryman in any Pokémon Center.
    Mewtwonite Y  x1                     Serial Code  |  Mar 03 to Oct 31, 2017  |  KO 3DS: SM 메가스톤 선물 •뮤츠나이트X
•뮤츠나이트Y Format Ver.v1.0.5, Post Updated Date:20173509_1635

This gift was given away to participants of the 2017 International Challenge (February Competition).
Participants were required to take part in at least 3 battles of the Online Competition, with a game synced game and account.

This event will then be given away via common password at a later time.
Distribution Title 메가스톤 선물 Wondercard ID 1606     Games SM Type Serial Code Distribution Date Mar 7 - Apr 27, 2017 Item Mawilite Quantity x1 Bundled with Beedrillite x1 Receiving Text 0x2C Thank you for playing Pokémon! Please pick up your gift from the deliveryman in any Pokémon Center. Distribution Text
•입치트나이트
•독침붕나이트  

From the period of February 28th to March 13th, there was a Global Mission to earn 250,000 Battle Points at the Battle Tree.
When the mission succeeds, players will receive 2,000 FC.
If the player earned 3 BP, with an account Game Synced with PGL, they will get 5 Rare Candies.
Furthermore, if 500,000 BP was earned globally, a Heavy ball will come bundled with the 5 Rare Candies.
The final count for the mission was 15,671,838 BP earned.
Distribution Title 포켓몬 글로벌 링크 Wondercard ID 1607     Games SM Type Serial Code Distribution Date Mar 21 to Apr 27, 2017 Item Rare Candy Quantity x5 Bundled with Heavy Ball x1 Receiving Text 0x38 This is a gift from the Pokémon Global Link! Please pick up your gift from the deliveryman in any Pokémon Center. Distribution Text
글로벌 어트랙션 참가 기념 선물입니다!

This gift was given away to participants of the Regional Rumble: Kanto X Alola (2017 March Competition).
Participants were required to take part in at least 3 battles of the Online Competition, with a game synced game and account.

This event will then be given away via common password at a later time.
Distribution Title 메가스톤 선물 Wondercard ID 1608     Games SM Type Serial Code Distribution Date Mar 28, 2017 to ? Item Pidgeotite Quantity x1 Bundled with Steelixite x1 Receiving Text 0x2C Thank you for playing Pokémon! Please pick up your gift from the deliveryman in any Pokémon Center. Distribution Text
•피죤투나이트
•강철톤나이트

From the period of March 28th to April 10th, there was a Global Mission with the goal of collectively hatching 200,000 eggs.
When the mission succeeds, players will receive 2,000 FC. (failure resulting in 200 FC)
If the player hatched 3 eggs, with an account Game Synced with PGL, they will get 5 Rare Candies.
Furthermore, if 400,000 eggs was hatched globally, a Love Ball will come bundled with the 5 Rare Candies.
The final count for the mission was 14,503,078 eggs hatched.
 
Distribution Title 포켓몬 글로벌 링크 Wondercard ID 1610     Games SM Type Serial Code Distribution Date Apr 18 - May 30, 2017 Item Rare Candy Quantity x5 Bundled with Love Ball x1 Receiving Text 0x38 This is a gift from the Pokémon Global Link! Please pick up your gift from the deliveryman in any Pokémon Center. Distribution Text
글로벌 어트랙션 참가 기념 선물입니다!

From the period of April 25th to May 9th, there was a Global Mission to harvest 3,000,000 Poké Beans from Poké Pelago.
When the mission succeeds, players will receive 2,000 FC.
If the player harvested 30 Poké Beans, with an account Game Synced with PGL, they will get 5 Rare Candies.
Furthermore, if 6,000,000 Poké Beans was harvested globally, a Level Ball will come bundled with the 5 Rare Candies.
The final count for the mission was 75,230,246 Poké Beans harvested.
 
WC 1612: 포켓몬 글로벌 링크 Rare Candy
        x 5 0x38 This is a gift from the Pokémon Global Link! Please pick up your gift from the deliveryman in any Pokémon Center.
    Level Ball                     Serial Code  |  May 16 to Jun 29, 2017  |  KO: SM 포켓몬 글로벌 링크 글로벌 어트랙션 참가 기념 선물입니다!

Korean League 2016-17 WINTER
WC 1100: 큰금구슬 선물 Big Nugget
        x 1 0x2B Thank you for coming to the Pokémon event! Please pick up your gift from the deliveryman in any Pokémon Center.
                          Infrared  |  Dec 17, 2016 - Dec 18, 2016  |  All Regions: SM 큰금구슬 선물 「포켓몬스터썬・문」첫번째 선물!
반짝반짝 빛나는 큰금구슬을 선물합니다.
상점에 비싸게 팔아서 원하는 도구를 사보자!
Event wasn't contributed by photo-user above; image is here purely to validate the distribution text.

From the period of May 30th to June 12th, there was a Global Mission for players to successfully hook 500,000 Pokemon or items (combined count) from rare (fishing) spots.
When the mission succeeds, players will receive 2,000 FC.
If the player have 3 successful hooks, with an account Game Synced with PGL, they will get 5 Rare Candies.
Furthermore, if there is a total of 1,000,000 successful hooks globally, a Lure Ball will come bundled with the 5 Rare Candies.
The final count for the mission was 1,228,170 successful hooks.
 
WC 1615: 포켓몬 글로벌 링크 Rare Candy
        x 5 0x38 This is a gift from the Pokémon Global Link! Please pick up your gift from the deliveryman in any Pokémon Center.
    Lure Ball                     Serial Code  |  Jun 20 - Jul 30, 2017  |  KO: SM 포켓몬 글로벌 링크 글로벌 어트랙션 참가 기념 선물입니다!

From 15th July (Sat) to 23rd July (Sun), Eevee Friends was distributed via Infrared,
to players that visited the Pokemon Pop-up Store at Hyundai Department Store Shinchon Station Underground 2F Connection Passage Graduation Tempyo.
This is a once per day event, meaning it'll take 8 different days to collect all the Eeveelutions.

This page has the WC7 and also photographs of the physical location, courtesy of @BLACKBIRD & @katsuya!
 
Distributions of the same event:
               

From the period of July 25th to Aug 09th, there was a Global Mission for players globally to win the lotto 1,000 times.
When the mission succeeds, players will receive 2,000 FC.
If the player draws one lotto (doesn't have to be a win), with an account Game Synced with PGL, they will get 5 Rare Candies.
Furthermore, if there is a total of 4,000 times the lotto was won, a Fast Ball will come bundled with the 5 Rare Candies.
The final count for the mission was 30,256 wins.
 
WC 1623: 포켓몬 글로벌 링크 Rare Candy
        x 5 0x38 This is a gift from the Pokémon Global Link! Please pick up your gift from the deliveryman in any Pokémon Center.
    Fast Ball                     Serial Code  |  Aug 15 to Sep 30, 2017  |  KO 3DS: SM 포켓몬 글로벌 링크 글로벌 어트랙션 참가 기념 선물입니다!