On its own, that'll give all your other creatures infinitely high stats, which is certainly not a bad place to be
Give Mulldrifter an Evoke ability where you can simply draw 2 cards for 3 mana and now we have excellent blue card draw options
Finally, if youre looking for something a bit more high impact, there are a number of mass-reanimate spells available
It isn't so much that it is good, just that it scales with the goodness of what your opponent is up to and with cube having all the best cards being able to exile one for 3 mana is pretty tasty
These two creatures each need to go in a fairly specific build, but they are each fairly good, if somewhat niche cards
It's not as if anyone is dying for Chaos Orbs for the sideboard of their Legacy Soul Sisters deck or their next Vintage Magic Night at the local game store