Unlock the following characters by performing the corresponding tasks:
HOW TO UNLOCK
In 199X, catch up to her.
Start the final mission.
Collect 100% of the Glorbs.
In 9,600 BC, reach the waterfall with the falling logs. Ride the logs down instead of moving up, then jump to the bottom right corner of the area to find a door. Shoot it open and kill the enemy inside.
In 198X, search for his cage behind a large gate. An enemy robot will drop down. Quickly defeat the robot before it kills Jef to save him.
Lou Don Jim
In 3072, blow open the vent cover and enter the hallway. While avoiding the fires, look for a breakable floor. Destroy the panel, followed by a second panel to find Lou.
In 199X, enter the pit at the base of the large tower in the far right of the area and kill the creatures before Melanie is lowered into them.
In 673, reach the point where the path under a large spiked gates splits into an underground cavern then quickly go down and kill the executioner before he kills Merlin.
Collect all the Shards.
Collect 50% of the Shards.
Collect 50% of the Glorbs.
Complete all Looker Time Trial challenges.
In 1,000,000 BC, you will encounter Zack tagging dino eggs before reaching the Boss. Defeat the killer dinosaurs to save Zack.
Complete all seven levels and defeat the last Boss to unlock the "Super Hardcore mode" option at the main menu. This mode gives you access to any characters unlocked in Normal mode. However, each time a Super Time Force member dies, they will remain dead until you have "saved" through their original unlocking process.