BY CRISTINA KINON
DAILY NEWS STAFF WRITER

Friday, February 15th 2008, 4:00 AM

 Wolf (aka Don Yates) has been getting ready for the final showdown on 'American Gladiators.'

The first high-octane season of the reincarnated "American Gladiators" on NBC is coming to a close, but there's one last two-hour showdown this Sunday at 7.

"It's definitely going to be the most interesting show yet, because [these competitors] are the best," Gladiator Siren told reporters in a conference call. "They're the cream of the crop."

The top male and top female competitor who make it through challenges like the Joust, the Wall, the Assault and the Eliminator, will walk away with the $100,000 top prize and the opportunity to become a Gladiator themselves next season.

And though both Siren and fellow Gladiator Wolf think each of the four finalists is up to the task, they say being a muscle-machine in spandex is no walk in the park.

"It's different when you're a Gladiator and you have to put your game face on and give 100% effort every day for every single event," said Siren. "That's a lot different from just being a contender for a day."

To prep for such intense competition, these lean, mean fighting machines spend hours a day in the gym doing cardio and lifting weights.

"Siren and I were just in Gold's Gym the other day and I did 80 minutes of cardio before I did my actual workout," said Wolf. "And we body-slam each other during the off-season," joked Siren.

But being in shape is only part of what makes a Gladiator so ferocious. They also have to have an intimidating nickname and, of course, the skin-tight uniform.

"There's a professional designer [for the costumes] and he did a phenomenal job," said Siren. "We just tweaked them to fit us and made sure they were flattering and comfortable. I didn't want to wear shorts that were riding up when I was competing on national television."

Though the Gladiators might seem like a scary bunch, they say that the atmosphere in the locker room is more like family than an every-man-for-himself situation.

"You got to let your ego go in this kind of sport," Siren said. "It's like a professional sports team, if you let your ego get in the way and you want to be the star on your team, then you're really not a team player and your team's not going to go as far ... we're just there to support each other."

And for Wolf fans, here's something you might not know: The howling man has a soft side (even though he's broken over 130 bones and been gored by a bull).

"From the time I was 7, I wanted to grow up to be Elvis," Wolf said. "I'm eventually going to put an album out because I love singing. And [I want to] act, and do everything. I'm also into helping kids find themselves."

Just not when they're staring down the barrel of his Assault air cannon."