By entering the Labyrinth God's Gift is contacted by Chlotz via the Vis-O-Matic and explains, that he is now allowed officially to use that gadget.
This is also stated by Ruby Coiler, but after she leaves Chlotz tells his friend that Mark Flask and some scientists also have entered the labyrinth. Chlotz askes him to pay attention that Mark and his men will be unharmed.
As God's Gift is exploring the labyrinth, he meets Mark on the fifth floor - he and his men are being attacked by monsters. None of them has a clue how to defeat the beasts and scream for help. God's Gift decides to save them and fights the monsters. Here a boss battle against one Laboratos and two Fornax occurs - all of the three are by the element fire.
After Mark and the others are saved, Mark explains that they where testing a new invention, but that he can't speak about it. (it's most likely the Neo Ether). After that, the men leave the Dungeon.
On the last (eighth) floor he has to fight the Dusk Spawner: Mammon. After the fight is won, he sterilizes the labyrinth by sealing Mammon.