Note: Made it for personal use. Still experimenting around with it but it's gotten pretty satisfying to use at this point.

It feels sluggish at first, but it will get crazy fast once it builds a bit of combo (which increases passive duration). It doesn't have attack speed mods but trust me, it doesn't need them.

How to use:
Just use regular melee until Tennokai pops up, it takes a bit to "warm up" ([Pennant]'s passive + 12x Combo), but after it warms up it will pop Tennokai very often (because of [Discipline's Merit]) and attack very, very fast. At max combo its passive atk spd stacks last 46s each.
Try to not use Heavy Attacks outside Tennokai to save up combo, use it only to get a bit of attack spd early on.

More info on how it works in the wiki.

Went for Heat + Range with the Riven for some crowd control, more DoT and the 50% armor strip.

P.s.: I made it look like Sam's Murasama from MGR, it even has the fire from that first cutscene because of the riven lol