2.5th Anniversary - Operation: Welcome to Sekai!!

2.5th Anniversary - Operation: Welcome to Sekai!! ([2.5周年記念]セカイへようこそ大作戦！！) is a special campaign running from March 30, 2023 12:00 JST to April 20, 2023 23:59 JST. This campaign was launched as a part of Project SEKAI's 2.5th Anniversary to invite friends to come play Project SEKAI.
== Campaign details ==
Participating in the campaign depends on whether the player is considered new or not. Players are considered a "veteran player" if their account cleared the game's tutorial before March 30 at 11:59 JST and are considered a "new player" if their account completed the tutorial after March 30 at 11:59 JST.
For veteran players, they will need share their invite codes to newly created accounts (the new players). The new players will then enter these codes in game and complete 3 missions. For each mission completed, this player will be rewarded with different items. Once all 3 are completed, the referring, veteran player will then receive referral rewards, depending on how many players they've invited and how many of these invited players have completed all 3 missions.
For veteran players, once the first player that they've invited has completed all 3 missions, they'll receive one Friend Invitation - Guaranteed 4☆ member gacha ticket. This gacha ticket can be used to pull in the Friend Invitation - 4☆ Guaranteed Gacha. From each additional player, they'll receive 50 fragments of feelings. Rewards cap at 10 players, so the maximum amount of rewards for a veteran player is 1 gacha ticket and 450 fragments of feelings.
 Veteran player missions
# of players invited	Reward
1 	
2-10 	per player
For new players, they'll receive a different reward for each mission completed, with the final reward being the same Friend Invitation - Guaranteed 4☆ member gacha ticket that veteran players received. By completing all 3 missions, new players will receive 300 fragments of feelings, 300 crystals, and 1 gacha ticket.
 New player missions
Mission 	Reward
1 unit main story read 	
2 unit main stories read	
3 unit main stories read	
Rewards are automatically added into the inventory. Veteran players have until April 30 to claim all their rewards.
== Veteran players ==
For veteran players, they can find their invite code by clicking on a banner with Miku waving in the home screen. This will bring up the page with the invite code, as well as the number of new players recruited.
File:2.5th Anniversary - Operation Welcome to Sekai!! banner location.png | Banner location
File:2.5th Anniversary - Operation Welcome to Sekai!! veteran player campaign page.png | Veteran player campaign page
Once an invited player has completed all 3 missions, a popup will be shown the with rewards for the now complete mission and the player who completed it. The green button on this popup will open another popup that allows the veteran player to send a friend invite to the invited player. The campaign page will also be updated with a new mission in progress (if there is one) and the new number of invited players with all 3 of their missions complete.
File:2.5th Anniversary - Operation Welcome to Sekai!! veteran player reward received with option.jpg | Popup showing rewards received with an option to send friend request
File:2.5th Anniversary - Operation Welcome to Sekai!! veteran player friend request.jpg | Popup for sending a friend request
File:2.5th Anniversary - Operation Welcome to Sekai!! veteran player mission 1 complete.jpg | Campaign page with mission 1 complete 
Veteran players must log in before March 30 to receive these rewards, as they will not be in the Present Box, but sent to the inventory directly.
== New players ==
For new players, they can find the place to put the invite code they've received by clicking on the same banner with Miku waving.
File:2.5th Anniversary - Operation Welcome to Sekai!! banner location.png | Banner location
File:2.5th Anniversary - Operation Welcome to Sekai!! new player campaign page.png | New player campaign page
Once on the campaign page, players will need to tap the "コードを入力" button to open the invite code prompt. Once entered, the game will display a confirmation prompt showing the invite code on the first row and the veteran player that the code is associated with on the second row. Once confirmed, the "コードを入力" button will become greyed out.
File:2.5th Anniversary - Operation Welcome to Sekai!! invite code input prompt.jpg | Invite code input prompt
File:2.5th Anniversary - Operation Welcome to Sekai!! invite code confirmation prompt.jpg | Invite code confirmation prompt
File:2.5th Anniversary - Operation Welcome to Sekai!! new player campaign page updated.jpg | Campaign page with an invite code registered
Once registered, new players can now start making progress on their missions (details are in the campaign details section). Main stories are considered "read" once all chapters are complete and every chapter is read without using the "skip" or "fast forward" buttons. Reading starting from a bookmark will also be considered as a "skip". However, "auto" still counts as reading the chapter. 
For those who wish to speedrun the reading, the table shows the approximate time taken by manually tapping through the story and by using the "auto" feature. The "auto" feature will play the entire the MV, however, watching this can be skipped by tapping; watching the entire MV is not considered a requirement for reading the story. Because the VIRTUAL SINGER main story is only fully unlocked after reading all the other units' stories, read times will not be listed.
 Unit story read times
Unit 	Manual 	Auto
Leo/need 	30 minutes	2 hours, 23 minutes
MORE MORE JUMP! 	? 	2 hours, 37 minutes
Vivid BAD SQUAD 	? 	2 hours, 32 minutes
Wonderlands×Showtime	? 	2 hours, 37 minutes
25-ji, Nightcord de.	? 	2 hours, 32 minutes
Once a main story is read, a popup with the rewards for the now complete mission will been shown. The campaign page will also be updated with the mission progress for each main story read.
File:2.5th Anniversary - Operation Welcome to Sekai!! new player reward received.jpg | Popup showing rewards received
File:2.5th Anniversary - Operation Welcome to Sekai!! new player mission 1 complete.jpg | Campaign page with mission 1 complete
File:2.5th Anniversary - Operation Welcome to Sekai!! new player mission 2 complete.jpg | Campaign page with mission 2 complete
File:2.5th Anniversary - Operation Welcome to Sekai!! new player mission 3 complete.jpg | Campaign page with mission 3 complete
== External links == 
* Twitter announcement