viriss - Well, I already made the joke, but it's a good assessment of the card as well. This is a great example of how to use Silver Border on custom cards. Definitely playable design, but mechanics that would definitely not show up in Black Border. A land that cares about the month is a great silver mechanic as well. Crowfall might be a little powerful, but it's silly and thematic, which is just what you want for an Un-card.
Nonagon Infinity - First of all, just to get this out of the way, I know that "sanctuarize" is a real word, but it's one of those obscure ones that sounds made up. As far as mechanics go, I like that it makes you choose between a sanctuary and your land for the turn, though I think the wording leaves it a little awkward, in that it also preculdes cards that give additional land drops. Being both a Landfall and a Constellation trigger is interesting, but dangerous as well. It helps that it's not a land that sticks around, but that also means that, ultimately, this keyword's primary use is going to be ETB cheese.
Unfortunately, we didn't have more entries, so the winner is going to be Viriss.
I debated on whether this should enter tapped or not. Ultimately, the choice came down to three things.
1. Unless you're using zero-cost artifacts, you're going to lose some mana overall on its second ability.
2. The second effect is already limited to artifacts, which don't use as much colored mana to begin with, and for free that can only be spent on artifacts is considered fine on a card that enters untapped.
Phyrexian Forgery Legendary Land : Add . , Sacrifice an artifact: add . "It is frightening how much about the phyerxians has changed, and yet how much has stayed the same. Or rather, which things have stayed the same." --Karn
Quelzop, Bog of Terror Legendary Land : Add . , Pay X life: Quelzop, Bog of Terror becomes an X/X black Horror creature until end of turn. It’s still a land. ------------ Quelzop’s Immortal Call Legendary Instant (You may cast a legendary instant only if you control a legendary creature or planeswalker.) Gain life equal to the greatest ammount of life lost by a single player this turn.
"It's not difficult to make Magic players feel smart." - Mark Rosewater
Furthermore, I consider that Carthage must be destroyed.