Island Mode is unlocked after beating Danganronpa 2: Goodbye Despair for the PS Vita and PC. The game serves as a dating sim, leading the player through a version of the main plot where there are no mutual killings.
The game starts out identically to the beginning of the main story, where Hajime Hinata wakes up on the beach, and meets Nagito Komaeda who tells him that Usami is waiting for them at Jabberwock park. The two then head there and find the other students, along with Usami yelling at someone to come out. Once again, Monokuma appears on top of the statue, however this time, Usami is ready and attacks Monokuma before he can finish his introduction and defeats him, forcing him to leave the island. Without Monokuma, the group is free to bond together over the course of 50 days, while building the assigned objects for Usami.
On day 51 the students say their goodbyes, discovering the strong bond they have built over the time together.
A player's goal is to collect all Hope Fragments missing, which naturally were not all maxed out during the main plot. You are given 50 days, of which several are so called "Holidays", which are exclusive made for bonding. During work days Usami will assign projects for the group, which do not necessarily have to be finished, yet will rewarded with gifts. Students have a maximum collecting and cleaning level of 9, which can be maxed during several instances of the game mode. While it is possible to collect all Hope Fragments in the first playthrough, it appears certainly hard to finish Usami's final task due to the lack of levels for your students. Upon finishing Usami's final task, you will receive Monocoins.
Each individual character can be assigned a daily task, which include resting, cleaning or gathering materials in the 10 different featured locations. Gathering materials will slowly consume each student's energy, as well as slowly reduce the island's cleanness. Resting for the day will not provide materials to build backups, but it will also prevent the "Cleanness" gauge from falling any faster. Assigning the cleaning task will fill up the cleanness gauge again. If the gauge becomes empty, the students will be forced to clean, wasting a few days.
Construction will display all owned materials and what you have created from them, along with the next goal. It's divided in four categories: Goal, Tools, Consumables and Processed Goods. "Goal" will display the materials needed for the goal received from Usami. Tools is a collection of tools which can be built to increase the students' stats such as reduce health cost, increase cleaning effect and increase gathering yield. Consumables are food you receive from Usami herself or cook by using your own materials. They can be used to refresh the students' health, increase levels and automatically clean the island. Processed Goods are materials created from others and are used to further proceed in building your goals.
The goals Usami assigns you during the game are:
1x Flower Pin
2x Gorgeous Flower Pin
1x Usami House
8x Usami Strap
10x Usami Coin
2x Jabberwock Bling
1x Good Ship Usami
The Personal Effects option gives a quick overview over the students' levels and health situation. It allows you to refresh health by using food, increase levels or wake unconscious students. This feature should normally be checked before assigning tasks as a lack of health points will end in losing work days should students get too exhausted.
The player will be given the opportunity to raise Hajime's "love" with another student. If the player manages to build the assigned object, Usami will provide the player with "Trip Tickets", which can be used to take another student on a "date". Each character can grow up to a maximum level of 10 hearts. The individual responses during the date will raise the affection for a full of half a heart depending on how much the character liked your statement. On day 51 Hajime will speak to the characters with maximum love, receiving a special ending. Upon restarting Island Mode the love levels will reset, however previously maxed relationships receive a heart mark and do not have to be repeated. Upon maxing out all characters the player is awarded with an achievement.
Shot Through The Heart
Shot Through The Heart is a minigame in island mode. It uses mechanics used in the Rapid Fire Debate trial minigame in the main plot. After gaining a "Trip Ticket" from Usami and using it to go on a trip with another student, Hajime is given an insight into their mind, and is given the ability to reply to the student's thoughts by shooting a "Affirmation" or "Negation" bullet. Replying to the right thoughts with the right responses will earn a step forward towards getting their ending. Unlike the Rapid Fire Debate, there is no time limit.