Here is an overview of the game, via its official website:

About

DARIUSBURST CS Core + TAITO / SEGA Pack includes only the “CS Mode” and “DLC Mode” from DARIUSBURST Chronicle Saviours, which is available on other platforms. (The various modes within “AC Mode,” such as “Original,” “Original EX,” “Chronicle,” and “Event,” are not included.)

CS Mode

• Six New Areas – The Switch release adds six new areas to CS Mode, allowing players to enjoy a magnificent chronicle of all 225 areas starting from Darius year 1906:
  • Darius (1904/06) – Open War: A new scenario themed after the original DARIUSBURST featuring Riga Pratica and Ti2.
  • Wafuo (1911/10) – Assault on the Cosmic Graveyard: A new scenario based on the additional event from DARIUSBURST: Another Chronicle EX+.
  • Darius (1914/12) – 6th Interplanetary Conquest: A new scenario based on the additional event from DARIUSBURST: Another Chronicle EX+.
  • Taimi (1910/10) – Cosmic Fissure Belt: A new scenario based on the additional event from DARIUSBURST: Another Chronicle EX+.
  • Irukehota (1910/08) – A new high-speed stage without a scenario.
  • Sunamau (1906/06) – A burst counter tutorial stage.
• Replay Mode – In addition to a leaderboard that lists the top scores across each mode, there is also a Replay Mode that allows you to replay the top players’ moves. You can download the replay data of the top player across each mode.
• Ghost Score – When playing a stage for which you have downloaded replay data, your replay score will be displayed as a Ghost Score. You can aim to improve your score by checking the difference in score with the top player. (You can select either the top player’s score or your own score to use as a Ghost Score.)
• Experience the Vibration of the Arcade Cabinet via the Controller – One of the main appeals of the arcade version of DARIUSBURST Another Chronicle is the powerful vibration created by the speaker built into the seat of the arcade cabinet. And for DARIUSBURST CS Core + TAITO / SEGA Pack, you can experience that vibration via the controller.

DLC Mode

In this mode, you can play with both the aircraft of Darius and those of various collaboration titles from TAITO and SEGA. Each pack contains the following units:

• TAITO Pack
  • Inter Gray (Night Striker)
  • Black Fly (Metal Black)
  • X-Lay (Rayforce)
• SEGA Pack
  • Harrier (Space Harrier)
  • TRY-Z (Galaxy Force II)
  • OPA-OPA (Fantasy Zone)