There are no major differences between the Level S version and Special Interceptions for Gravedigger.
The main things to remember about Grave Digger are the following:
Failing to break the red circles for 2 cycles will cause a heavy damaging attack that will break your shield and deal heavy damage to your HP.
Every second set of circles to break will spawn 2 drills that will randomly target one of your units, the drills in this version of the interception deal more damage and stun.
From stage 7 onwards, Grave Digger will enter it’s last phase changing the QTE circles.
Priority should always be to destroy the drills first before breaking the circle. Every drill spawn should line up with your burst so that they break instantly, and you have time to break the circles.
It is more than likely that you will tank at least 1 drill attack, unless your damage is consistently high for most of the fight.
Recorded 03/14/2023 – Pre BowWow Patch by me
Credits to Tenka
Credits to Merkuria