The fourth set in the Dash series introduces the Fusion System (Japanese: 合体システム), which allows certain Pokémon when used together in battle to fuse into a different form. One of the launch courses includes a Grade 5 Necrozma with the Fusion (Japanese: がったい) ability, allowing it to fuse with Solgaleo or Lunala from previous sets to respectively form Dusk Mane Necrozma with the moveSunsteel Strike or Dawn Wings Necrozma with Moongeist Beam. While in these forms, Necrozma receives a boost in stats relative to the Grade of Pokémon it fused with: Grade 5 disks will boost Necrozma's Energy value by 1,040 points, while Grade 4 or Special disks will boost its Energy value by 760 points. If Solgaleo or Lunala disks with access to their exclusive Z-Moves are used to fuse with Necrozma, it can use these in battle as well. A new Grade 5 Kyurem, also with the Fusion ability, could be encountered on a course available to play from March 15, 2018. Kyurem can fuse with Reshiram to form White Kyurem with the move Ice Burn or Zekrom to form Black Kyurem with Freeze Shock. Players cannot use another Pokémon while Necrozma or Kyurem are in a merged state as both disk slots on the console will still be in use. Pokémon in a merged state cannot be distributed as a single disk.
The Let's Begin Ga-Olé! Course, a beginner course that has featured in the starting lineup of every Dash series set, had its roster expanded for the first time since the start of the series. These new additions were the two Cosmog previously available in the Let's Raise Cosmog! Course from the second Dash set. Among other courses available to play for the duration of this set was the Regigigas Course, in which players could encounter and capture a powerful Grade 5 Regigigas as well as Grade 4 versions of the Legendary giantsRegirock, Regice, and Registeel. The Poipole Special Course and Naganadel Course introduced the first Ultra Beasts to Pokémon Ga-Olé in the form of Poison Pin Pokémon Poipole and Naganadel; the latter course also included another Grade 5 Silvally, this time with a Psychic Memory. Two new Grade 5 Lycanroc could also be encountered on the last of the standard courses available to play for this set, each of them with access to the exclusive Z-Move Splintered Stormshards.
Trainer and Battle Mode was available to challenge from March 29, 2018 and provided a new roster of opponents to battle. These opponents included 2 new Trainer classes and a new Battle Leader, Ratsuha, who could be challenged upon defeating the 4 Trainers before her. Promotional Regigigas or Darkrai disks could be dispensed for an additional ¥100 following a battle with Ratsuha, with 'WINNER' versions available to those who successfully defeated her entire team.
Tyranitar and Magnezone were added as Support Pokémon from this set. Players registering a Ga-Olé Pass for the first time would automatically receive Tyranitar as a Support Pokémon as part of the Pokémon Ga-Olé Welcome Campaign.
Fusion!! Necrozma Course
Playable at set launch
Let's Begin Ga-Olé! Course
Playable at set launch
Playable from March 1, 2018
Fusion!! Kyurem Course
Playable from March 15, 2018
Playable from March 29, 2018
Super Strong! Lycanroc Course
Playable from April 12, 2018
Available for Pokémon Ga-Olé Members to redeem from February 15, 2018 for 1,000 Member Points
Volcanion & Fire Friends Course
Playable from February 15 to July 31, 2018
Available as an insert in the April 2018 issue of CoroCoro Ichiban!, released on February 21, 2018
Groudon & Earth Friends Course
Playable from February 21 to April 25, 2018
Available as an insert in issue 57 of Pokémon Fan, released on February 28, 2018
Kyogre & Water Friends Course
Playable from February 28 to April 25, 2018
Special Regigigas Course
Playable from March 1 to 25, 2018 on select units
Available as an insert in the April 2018 issue of CoroCoro Comic, released on March 15, 2018