Absolutely dirty run, each mana gives +2 to the spear, frog totem refills 3 mana per turn
had a similar run that let me give these arrows +2 and use them all at the same time with the bow, this screenshot is from earlier in the run but later on I got 5 arrows around the ring and was getting +10 from each use of the ring
there's also arrows that get more damage per manastone connected but I didn't find any this run but still my highest damage run yet.