If you hold down "e", you can walk through the walls on the first story mission since it stops checking collision
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Mission 2: stepped on the little port warehouses, catapulted to the stratosphere. 10/10 unironically. PS: since in your lore it is unclear wether the natives worshipped you as a god or a demon, and there are other native buildings throughout the other levels, maybe you could tie it in the end as the end of the final mission, where wether or not you spared the native culture you get one ending or another.