To be in Go Mode means that the player has collected a set of items and/or characters that will allow them to complete the game. Jets of Time has three different Go Modes, all with different requirements:

Collect the Gate Key, the Dreamstone, and the Ruby Knife. Enter the Tyrano Lair in 65,000,000 BC and defeat Black Tyrano, then proceed to Zeal Palace in 12,000 BC, enter the Ocean Palace, and defeat Lavos. If you are defeated by Lavos, you may watch the cutscenes and then use the bucket at the End of Time to re-engage Lavos or crash the Epoch into its shell.

• Gate Key: Grants access to Prehistory (65,000,000 BC)
• Dreamstone: Place on the button in Kino's cell in the Tyrano Lair to unlock the upper levels.
• Ruby Knife: Opens the sealed door to Queen Zeal's throne room and the path to the Ocean Palace.

Collect the Pendant, the Chrono Trigger, and the Clone. Enter Keeper's Dome in 2300 AD and speak to the Nu in the back room who will release Poyozo Dolls to Death Peak. Now, you may enter Death Peak. Complete Death Peak and watch a cutscene during which the Black Omen will rise. Enter the Black Omen from 12,000 BC, 600 AD, or 1000 AD. Complete it and defeat the Mammon Machine and Queen Zeal to roll the credits. In standard flagsets (with the z flag), Queen Zeal will be the final boss and you will not need to face Lavos after defeating her.

• Pendant: Grants access to the Future (2300 AD) and opens sealed doors and chests (in standard flagsets with the p flag, the Pendant will already be charged and there is no need to take it to the Mammon Machine first)
• Chrono Trigger: When given to Belthasar's Nu along with the Clone, grants access to Death Peak.
• Clone: When given to Belthasar's Nu along with the Chrono Trigger, grants access to Death Peak.

Collect the Broken Sword and Broken Hilt and recruit Frog into your party. Take the two sword pieces to Melchior in 1000 AD and he will repair the Masamune. Bring Frog to the Magic Cave in 600 AD and watch the cutscene, after which you will be outside Magus's castle. Completing Magus's castle will grant access to 12,000 BC and open the door to Queen Zeal's throne room. Enter the Ocean Palace, and defeat Lavos. If you are defeated by Lavos, you may watch the cutscenes and then use the bucket at the End of Time to re-engage Lavos or crash the Epoch into its shell.

• Broken Sword: Half of the Masamune. Bring it to Melchior along with the Broken Hilt and he will forge the Masamune for you.
• Broken Hilt: Half of the Masamune. Bring it to Melchior along with the Broken Sword and he will forge the Masamune for you.
• Frog: Once you have the sword, bring him to the Magic Cave to open Magus's Castle (while it was once required that he have the Masamune equipped, this is no longer the case).