Mace Windu applies the Shatterpoint debuff (+100% Defense Penetration) to a character, which looks like a red version of the "Advantage" buff.
This debuff lasts for one turn, and can be removed by casting any buff on the affected character.
A list of basic tank abilities that most players should have:
- First Order Stormtrooper - The Order Relentless (self buff)
- Clone Wars Chewie - Defiant Roar (self buff); Wookiee Resolve (Leader, level 3, self buff on whoever procs it)
- Royal Guard - Imperial Phalanx (team buff)
You can also use Chewie's taunt if an ally has the Shatterpoint debuff with no way to cleanse it in order to prevent Mace Windu from one shotting them.
Finally, attacking the support droids will reset their turn meter, preventing them from helping Mace Windu.