Rupture Summon build by Cliptis - rotation?

I’m trying to follow his guide, and at the end of the video he showcases 1-shotting Belial as he’s explaining the rotation. He says something like, “…shouts, but only 1 shout…”

I’m confused as hell. I start with CotA, then Rupture, and then I’ve tried spamming all 3 shouts, I’ve tried casting just one shout, but I can’t do it correctly it seems. Does anyone play this build that can help me out?

COTA, Rupture, ALL 3 Shouts, then WW to proc Rage for CDs, then Rupture and just 1 shout (pref War Cry as you should extra levels in War Cry so CD is low). Technically not really one shot but Belial goes down quick. COTA esp from the quake is what does most of the damage. He’s got the rotation listed on his Mobalytics build.