Regrettably, Tithe is on the Reserved List, so it is ridiculously expensive for the effect you get, but if you want an inexpensive alternative that is slightly watered down, Gift of Estates plays reasonably well, trading instant speed and doubling its mana cost for a guaranteed 3 plains cards
Yes, there's people crazy enough to fill out an entire deck with Krakens, Leviathans, Octopuses, and Serpents, slapping a commander like Thassa, God of the Sea, Slinn Voda, the Rising Deep, or (my favorite!) Arixmethes, Slumbering Isle, and then smashing face with giant sea monsters
A commander all-star, priced fairly at over $20
On its own, Paralyze is not a reliable archetype for building a deck
Saheeli just keeps copying Felidar Guardian, which just keeps blinking Saheeli
Knock Out your opponents last Pokmon in play