No show me scan that says gaara doesn't use chakra to control sand in the desert how can he move and manipulate sand without chakra? That is absurd. If you read again when madara just get to the battlefield the sand he used is the desert sand. And how does gaara block their vision with sand? He can only block between himself and them nothing more he can't separate them. He can't attack from below the chakra in his sand get absorbed see above and pain rain no jutsu can cause problem for gaara's sand too.
you dont understand,it takes chakra to move the sand around,however,normals sand,contains no chakra inside it,hence it is not as fast as his gourd sand which has chakra inside it,just like how a normal punch cant have the same power as a chakra infused punch,but you cant absorb any chakra from a normal punch,but can absorb the chakra from a chakra infused punch. Thats the reason madara needed susanoo to break out of his sand coffin,cuz he cudnt absorb anything there,would gaara,after seeing preta from madara,still use a sand that can be absorbed?.
He can use his sand to seperate them,or atack them from below and above,sand hail will surely hit a few,if normals and is used,preta cant absorb it,hence deva is the only one who can protect himself,and if the paths are together,then his ST would blow them away too.
Gaara can attack all of them simyltaneously,their vision wont hel if they all have something to dodge,sand hail,flloed by an attack from below,coupled with a frontal sand drizzle then multiple sand arms,and at leats 3 paths are killed,missiles from asure isnt as powerful as the explosion and shockwave caused by a meteor. Deva has a 5 sec interval,gaara can attack him,and make him use ST,then follow it up with a quick sand coffin. He can have a sand clone handle human and naraka.
Within 8 minutes,konoha crater would become a konoha desert.