After putting together all three key parts in the ultimate weapon- it is ready.
You are now able to travel through time. Suddenly, monsters start swarming around you. You notice your cretaor's corpse lying in a mess on the ground, your only option is to travel through time. In a hurry you push the button and you are whisked away to another time period. However- unlike how you thought it was supossed to go, you traveled Back in time to a small lab. Even though the lab is small, you just happened to teleport into the worst place possible to be: The high-defence chamber. Survive long enough and gather back the traveling pieces blown up in the explosion.