If you like idle games, you should definitely check out the Monster Idle Factory. It's an idle game that's based on the concept of time travel.

The idea is that the world was in a state of law and order, but as the years passed by, people have grown reckless and without fear. In order to put everyone under control again, you will have to send minions back into time and they will have to bring you back artifacts containing the essence of fear.

Throughout the game, you'll be able to build new buildings and upgrade them. Also, you'll be able to enhance your items and your monsters.