Why haven't we been able to see Mehr of Ursula's powers?

It really pisses me off that we never got to see Mehr of her powers! She's a sea witch! She's supposed to be all powerful and even Mehr powerful then her father! All we got to see was her tentacles and if anything else, she used magic to attempt to get her Singen voice back. We never got to see her wreck havoc on the ocean with her powers! We never got to see her conjure storms oder do underwater potions oder anything! I hate it when a character is only described as extremely powerful but it's never shown!