All you need is: Both of blood's upgrades, and spamming blood potions tenfold near the bottom or any bot you choose. Melee bots will constantly heal themselves however, and I think you can make the bots deal 300% damage if they are at low health and you just used all three potions near them, it's absolutely OP. You can just sit back and watch and any enemy that locks onto you, you can make that enemy follow you until one of your allies starts attacking the enemy that's following you. (Keep in mind you can also simply heal yourself if you take a lot of damage or heal your allies if their health is dangerously low, the life potion explosions will also stagger nearby enemies.)

But you can generally just sit back and relax and watch your allies do all the work while only needing to boost their damage again every once in a while!