Overview

Saku is a powerful wall with a fantastic defensive typing, reliable healing, damage-over-time options, and surprisingly hard-hitting attacks. Saku has fantastic defensive stats as well as only two weaknesses in Fire and Toxic, the latter of which it can threaten back with strong Wind attacks amplified by its Air Specialist trait. If Saku acquires some defensive boosts, it can be particular difficult to knock out due to its reliable self-healing in Lifeful Sap. Running all of Saku's tools for stall takes up several technique slots however, meaning that if Saku is denied the chance to acquire defensive buffs. 
 

(1.3 DUKE'S NOTES - SAKU IS KINDA SNEAKING UP AS A BULKY OFFENSIVE BEAST NOW, GETTING STRONGER EACH PATCH. MIGHT BE FINALLY WORTH A LOOK.)

Saku quite enjoyed its conversion from a special attacker to a physical one, as it has a great defensive typing, some very nice STAB moves, high-BP coverage options, and great support options as well.

Air Specialist is opted for over Botanist because of Saku's more accessible wind options. When played with other wind tems, Debris Typhoon is a force to be reckoned with, though it can be swapped for Boomerang on sets that aren't played next to other wind tems often. Turbine is a hard-hitting option on turn 2, going ahead of some medium-speed threats, while Frond Whip and Narcoleptic Hit give Saku a pair of hammer blows to throw up against wind resists.

Saku loves basically every wind ally in the game, so I've listed some other allies here. Hazrat likes Saku's ability to wall winds and earths, as does Minothor, who can amp Saku with Purgation. Saku has plenty of natural bulk that can be amped up by tems like Kinu and Pigepic, who can even get Saku a Turbo Choreography to help it get ahead of threats.