Vegetable Blade

A lush bunch of vegetable fronds suddenly springs from the
ground in an unoccupied space you can see within range.
As a bonus action, a creature can pull the fronds from the
ground, revealing a root vegetable of your choice that has
been grown in the shape of a blade. For the duration, a creature
can use the vegetable blade as a melee weapon with
which it is proficient. The blade deals 1d12 slashing damage
on a hit (adding your ability modifier to the damage roll as
normal), and it has the finesse property.
Additionally, on subsequent turns, the wielder or one of
its allies can use a bonus action to take a bite out of the
blade. Doing so heals the creature for a number of hit points
equal to the blade’s damage die + your spellcasting ability
modifier. Once a creature has taken a bite out of the blade,
its damage die is reduced by one size—from a d12 to a d10,
for example. If the blade is reduced beyond a d4, it is
destroyed and the spell ends early.