Complete Healing is 400 mana. Manastone is 60 hp for 20 mana.
So you need to be able to manastone 20 times to break even on a complete healing cast.
So that's 1200 hp. Factor in the time it takes to manastone down, even though it's insta cast, plus the 10 seconds of complete healing, and you need about 1600hp minimum to even attempt to make it worth your while. Once you break 2khp it becomes pretty good. A low 50's cleric with gear focused on hp leveling in solb will never run out of mana.
'stuce
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