The deck that makes the most use of Solitude is probably 4c Elementals where it can be tutored up and then Ephemerated for some crazy value , but it is also vital for Azorius Control where it represents one of the few threats the deck can present
Combine this with the fact that you gain Water-type support cards such as Melony, and youve got yourself a huge archetype on your hands
Kenessos, Priest of Thassa This one might be more of a sentimental favorite since dear friend, fellow RC member, and Arixmethes, Slumbering Isle designer Scott Larabee has a Sea Monsters deck, which I enjoy pulling out the Mirror Strike for
Send 1 Machine monster from your Deck to the GY, whose ATK equals its own DEF, with a lower Level than that targeted monster, and if you do, the targeted monster gains ATK/DEF equal to the level of the monster sent to the GY x 100
Theres also the distribution of promo cards from both English and Japanese which could count as a set alone
Imagine that you have a lethal board full of creatures, but you're afraid your opponent will untap and cast a Fumigate to stabilize
