We’re at that place in progression where things need to start being combined. Like toboggan wake surfing or bodysurfing river waves.

Let us introduce the newest combination that will be the biggest hit in no time: skateboarding and slacklining.

Pro skater Sierra Fellers got together with skater/stuntman/gymnast William Spencer and the duo has been toying around with skateboarding and slacklining. They teased the possibilities yesterday with the above video of Fellers boardsliding a slackline. But that was only the beginning.

Today they dropped this little Instagram edit showing off their combined skateboarding/slacklining skills. Using their boards to bounce off the slackline looks incredibly difficult, and we’re sure there are probably some pretty painful slams involved in this.

But the bigger question is what do we call this newfound sport? Slackboarding? Skatelining? Truly, the possibilities are endless.

More about skateboarding from GrindTV

Tony Hawk joins the Lakai shoes team at the age of 49

Bam Margera and others to appear on Vice's new season of 'Epicly Later'd'

NBA champion Kyrie Irving talks about his love of skateboarding