Rarity's strength was quickly being sapped as she tried to move through the deep muck. Her legs sank deeply into the soupy earth, causing her to virtually swim for the nearest 'solid' ground. She'd kick out with her back hooves to bound herself over the next length repeatedly, until her tiredness wore out. The mud was too thick for her to trot through, and Rarity feared if she stayed still too long that she'd sink and drown in the swamp. 