Jump Scare isn't as flashy as the Endless Punishment deck led by Valgavoth, which was the most sought after commander from the Duskmourn set
Flavor questions aside, being able to recur this card from the graveyard sounds like a strong source of card advantage, especially if you have some mutate triggers already in play for it to benefit from
It remains one of the best blue cards MTG players can use to force a Do you have it? moment, often ending games as early as turn one with the right fast-mana support
She will distort threat assessment by building most of her power defensively (If you attack me, I can block with this giant creature with +1/+1 counters on it, If you attack me, I can chump block with My Breena deck primer on Moxfield (see that for more tips!) Dictate of Erebos out) until she reaches a point where her large evasive diplomats can crash in to finish off her opponents who are already weakened by the in-fighting and taxation
Otherwise you are Mind Twisting yourself, then it gets killed by a Heros Downfall or whatever