At the start of each round, Usuvu becomes ready to act. She can act only once per round.
Any player can spend an action to Command Usuvu: she gains two actions.
The player who commanded Usuvu decides how they are spent.
Instead of two actions, Usuvu can cast the 3-actions version of heal.
At the end of each round, if Usuvu hasn't acted, she will Raise Shield and Sustain any spell she had cast.
At the start of each round, Usuvu gains a reaction.
The GM decides how and when they are spent; usually, the first trigger to come up will be used.
13Perception
4 wis, 4 prf, 5 lvl
When rolling initiative, roll a DC 6 flat check. Either regain a spell slot, or cause a wellspring surge.