  3d mirrors for all 4d $\mathcal{N}=2$ Argyres-Douglas (AD) theories
engineered using 6d $(2,0)$ theory are found. The basic steps are: 1): Find a
punctured sphere representation for the AD theories (this is achieved in our
previous studies of S duality); 2): Attach a 3d theory for each puncture; 3):
Glue together the 3d theory for each puncture. We found the 3d mirror quiver
gauge theory for the AD theories engineered using 6d $A$ and $D$ type theories.
These 3d mirrors are useful for studying the properties of original 4d theory
such as Higgs branch, S-duality, etc; We also construct many new 3d
$\mathcal{N}=4$ SCFTs.
