Sacrificing your own creatures is, as already underlined, a big point in the deck, seven creatures target it
After all, we're looking at 6+ new sets for Standard every year
When you do, return Calim from your graveyard to the battlefield tapped
Hollow One and Vengevine might not be the best version of this archetype but its where I want to start
There are still fakes of the commons floating around, but youre far more likely to encounter a fake Enchanted variant in the wild
There's a smattering of cards that specifically interact with otters or make otters, and many of them are nice, efficient cards, even for a spellslinger deck with inexplicably few otters: Lilypad Village Valley Floodcaller Harnesser of Storms Otterball Antics Pearl of Wisdom Rockface Village Splash Portal Stormchaser's Talent Valley Flamecaller All of this adds up to an Izzet Prowess deck that features otters, which is awesome