Yes, in Box Shifter some free Unreal Engine Marketplace
assets were used to finish Box Shifter as fast as possible. Box Shifter was created in the course of a challenge to develop a mobile game within one week, with a budget of maximum 50,00€.
Box Shifter aims to show that it is possible to create a mobile game very quickly (if you want to). The game is also an experiment to find out how much advertising revenue you can earn with known advertisers without making the whole game full of ads. This challenge took place on @Der_Sky TikTok channel.