"It was nice to come out clean," said Rowena Duncum.
"My favourite part was running then doing diving belly flops."
Mats Vijay Menon and Phillip Pratt had a mud wrestle right at the finish line to decide who was going to carry the other over the threshold.
"It's super fun," said Menon, a expat Chicago native.
"The course is cool - cooler than I thought it was."
Pratt agreed.
"It's the dirtiest fun I'll have all weekend."
As well as the individual mud runners, there were teams of Oompa Loompas, Cavemen, Top Dudes, and then the bridal party of Shaun Jarman-Smith and his partner Rochelle Thompson.
"I decided [we'd enter]," said Jarman-Smith, as his group completed the course in their ceremonial outfits.
"Mum was on the phone, talking about the Mud Muster. Then Sonya [Joyce, bridesmaid] came up with the idea of doing a wedding thing."
While you may picture the groom helping his lady along through the tough stuff, Thompson said Jarman-Smith was the one doing it hard.
"He said, 'do you think you can do it?' [I said] 'yep'.
"You actually looked like you were going to die."
Sport Whanganui will use the same course next year.
Gallery
Individual results (Wanganui unless noted)
10km - Male: 1. Angus Mckelvie (Palmerston North) 49m 25s; 2. Josh Payne; 3. Neil Mayo; 4. Craig Wills; 5. Max Bell. Female: 1. Caitlyn Alabaster 1h 6m 31s; 2. Libby Abbott; 3. Emma Abraham; 4. Ellie Bowen; 5. Kelly Field.
5km - Male: 1. Matthew Camwell 28m 2s; 2. James O'Donnell; 3. Jared Lamont; 4. Dylan Amon; 5. Ben Wood. Female: 1. Mia Gemmell; 2. Heather Johnston; 3. Brittney Matthews; 4. Anna Robbie; 5. Rebecca Brown.
3km - Male: 1. Ben Lovecome 27m 3s; 2. Logan Nation; 3. Luke Wing; 4. Josh Jonas; 5. Ben Watkins. Female: 1. Sascha Donald; 2. Lisa Kennedy (Bulls); 3. Rachel Holcroft (Cambridge); 4. Rowena Duncum; 5. Rebecca Tonkin.