Fellas, let's take advantage of the gem gacha update. Let us consider.... Scathach. 15% A-frame Def debuff every 7 turns. 2 turns of guaranteed double attacks for herself every 8 turns. Replace Osiris with her in either configuration.
Gah, never mind. I forgot that Hastur is def down; thought she was atk down.
Put Puck in then for the single target berserk.
(assuming that you haven't rolled another R like Caspiel)