In Do Hard Shit, Spartan Master Coach Trevor Franklin attempts some of the hardest feats imaginable, all of which are complete surprises. You can watch the entire series now on Spartan's YouTube channel and on SpartanTV, and you can also watch them here.

Through three epic episodes of Do Hard Shit, Spartan Master Coach Trevor Franklin has conquered incredible feats and faced fears that he didn't even know he had, unlocking a new "hardest thing I've ever done" every time. After beating out a former Colts linebacker in the DEKA FIT arena, completing a 31-mile Ultra race in Montana, and getting pummeled at a Rugby United New York practice, it would be fair for Trevor to think himself capable of persevering to the end of absolutely any challenge that Episode 4 had in store. 

WATCH: Do Hard Shit, Ep. 1 | Do Hard Shit, Ep. 2 | Do Hard Shit, Ep. 3 | Do Hard Shit, Ep. 5

That's where he'd be wrong.

In Episode 4 of Do Hard Shit, Trevor takes on the Spartan Death Race, described by many as the absolute toughest race in the world — especially for your mind. Created by Spartan founder and CEO Joe De Sena, the roughly 72-hour race has been known to include events such as a 14-hour ruck, a 26.2-mile barbed wire crawl, a 50-pound sandbag carry over a marathon distance, pushing a 500-pound sled up the mountains of Pittsfield, Vt., and solving intricate riddles while severely sleep deprived. And similar to Do Hard Shit, Death Race competitors — only 10% of which have finished in the past 10 years — are not made aware of the challenges they'll face before they arrive on race day. 

Because racers are required to sign waivers stating they are aware that they may die during the three-day event, it's worth noting that Trevor did survive (and actually made it farther than anyone had expected). However, he did not finish. 

Related: Is the World's Toughest Race the Spartan Death Race?

Here are a few of the most grueling, shocking, and emotional moments from Trevor's Death Race, as documented in Do Hard Shit, Ep. 4. 

6 of the Most Intense Moments from the 2021 Spartan Death Race

1. Underwater Diving for Race Bibs ... Twice

The Death Race began at 6 a.m. Rain was already cascading down (as it would continue doing for much of the entire race), and immediately following registration, the racers were to scale a Tyrolean traverse with all of their race gear strapped to their back, drop into a freezing cold body of water below, and dive under the water to find a Death Race pinny yielding their racer number, which was weighed down by a 14-pound weighted vest. 

If that wasn't enough, Trevor had already forgotten his racer number when he dropped into the water. The no-bullshit nature of the Death Race should tell you that his solution — grabbing a random pinny and hoping for the best — simply didn't cut it, and registration sent the Master Coach back to the pond to give it another go before he finally had his own number on. Only then could the race really begin.

2. Carrying Two People, a Giant Tire, and a Portable Toilet up the Mountain

On the racers' first trip up the mountain, they were instructed to — as a group — carry a massive tire with one racer on top of it, and a portable toilet with one racer inside of it. And aside from the obvious intense physical demand of such a task, this event had an added mental component: memorizing a poem taped to the top of the porta-potty before summiting the mountain. This, Trevor said, is when his race really began.

"Having to work with others to do something that's strength- and endurance-based for a long period of time is stressful as can be," he said. "Most people that are here are pretty Alpha personalities. Everybody's trying to be the leader of the group."

Out of sheer exhaustion and subsequent miscommunication (not to mention being forced to remove their left shoe and continue on), the team carrying the tire dropped it (and the racer perched atop it) a total of three times. Thankfully, the hard-as-nails racer was not hurt, and they persevered on to the next event.

3. Drinking a Gallon of River Water

This one's self explanatory. Just a little over 24 hours into the race, the sun was rising and the racers were returning from a foot race where their shoes were filled with pebbles and they had to complete burpees at the finish line until the last racer finished. De Sena, who founded the Death Race, then instructed the remaining contestants — 13 remained out of 22 — to go to the river and fill their bucket with a gallon of water.

Then, they drank it. And yes, that included everything you might find in river water: pebbles, algae, minnows, insects — you name it. And as nauseating as that may sound, the racers were given no time to settle their stomachs, taking off immediately in pursuit of De Sena, who was jogging down a trail to the river, where they'd go for a morning swim. 

4. Picking 1,000 Stones from the River and Walking Them up the Mountain

The racers' main task for day two was to pick 1,000 rocks from the river, place them into their buckets, and walk them up an astonishingly uphill portion of the mountain that, although it was only about a quarter of a mile long, became extremely physically and mentally taxing when done over and over, all day long.

"This is the hardest mental battle I've had," Trevor said. "I'm in so much mental anguish. The second day around 3 p.m., that's when I started hurting. That's when I started seeing things. I felt like I was f****** losing it. I felt like I was high. I don't know a lot about sleep deprivation, but I know that it'll mess you up."

5. Performing a Play

With just a fraction of the original racers remaining, they were tasked with performing a play, or what Trevor called "the most annoying experience of my entire time on this farm."

All sleep deprived, physically exhausted, and mentally at their wit's end, the athletes dressed in white cloaks, wigs, and ferns, and — throughout a two-hour detour from hiking, running, and swimming — proceed to perform "Take a Chance on Me" by ABBA over and over. For someone in their state, that should have been enough to break even the most strong-willed person and make them question their sanity. 

6. A 24-Hour Hike and Puzzle-Solving Loop

After quite the performance, the race directors started a 24-hour clock — beginning in the darkest hours of the night — during which racers would have to complete as many loops of a mountain hike as possible. At the top of the climb, they faced a mental puzzle or riddle that they'd then have to uncover the answer to, hike back down the mountain while remembering their answer, and report it to those at the base before heading up for another loop. With a mind and body in perfect, restful condition this might be extremely challenging. For a person who hasn't slept and has barely been off their feet in days? It's borderline impossible.

"That is personally where I felt that I was — if not at — I was very close to my breaking point," Trevor said. "I'm exhausted, I'm hungry, I'm thirsty, my headlamp had died. That, right then and there, is when I feel like I kind of got to know myself a little bit better. That's when I uncovered my true self."

By the time the sun had risen, Trevor was disqualified for failing to meet the five- lap minimum that was required to advance. (He completed just under four laps.) However, the mental strength he gained on the mountain will be something he carries with him for the rest of his life (and the rest of his Do Hard Shit challenges).

"I think this experience is the only time in my life where I have truly been pushed to a limit, and found a new limit," he said.

Watch the full episode above, and stay tuned for episodes 5 and 6 of Do Hard Shit, coming soon.