Underrated combo
Aftershock (+Shield Bash) Ekko and/or Diana
Engaging with Ekko's stun procs Aftershock and gives him a shield. Using Diana's E triggers Aftershock and her W gives her 2 shields that stack, and I believe if you attack between the 1st and 2nd shield, Shield Bash will apply both before and after the 2nd shield, the second of which will scale with the combined shield size if applicable.
Both Aftershock and Shield Bash give bonus resistances which increases the effectiveness of the health the shields provide.
Their shields scale with Ability Power, so this still works with full AP or AP bruiser builds, with these runes it is difficult for them to be turned on when engaging.
and/or 