N (Sharpened)

Strategy and Synergy
Sharpened will positively increase the first four hits of the spell (+40,+30,+20,+10dmg respectively), however past the fifth cast, it will only reduce the spell damage each time it lands a hit. Intentionally missing may be considered to preserve the damage boost, but there are other alternatives.

For smaller decks, this upgrade may cause more trouble than help, mainly for -Decks, however it is a more manageable upgrade for the -only deck.

Large decks tends to not suffer too much from this upgrade however, since the spells tends to be cast less often.

This upgrade can combo with, by increasing the damage then doubling it, the spell afterward and preventing the damage penalty from subsequent use. With the appropriate artifacts and upgrades, you can combo those two even further to make powerfully devastating single-use spells.