Rules: Submit a card that meets the criteria
Grading Scale: None. I just decide which cards I like more

Criteria: Design a non-aura enchantment or an instant or sorcery that involves enchantments.
Round Ends: November 9th (Saturday)

Dark Seal
Enchantment
At the beginning of your upkeep, you lose 2 life.
Sacrifice Dark Seal: counter target spell.

Earthly Balance
Enchantment
At the beginning of your upkeep, if you control the least amount of lands, search your library for a land card and put it on the battlefield tapped. Then shuffle your library.

Ominous Shadows

Enchantment
At the beginning of each player's upkeep, put a fate counter on target creature that player controls.
Whenever a creature with a fate counter on it dies, draw a card.
"It seems they've taken an interest in you..."

Prayer's Gate
Sorcery
Search your library for an enchantment card with converted mana cost equal to or less than your devotion to white and cast it without paying its mana cost. Shuffle your library.

Cast primarily because the interaction with auras and shroud is intuitive, secondarily because of Heroic.

Ember Dance -
Enchantment
, tap an untapped creature you control: ~ deals 1 damage to target creature or player. The costs and damage of this ability are doubled each time it is used per turn.
Evoke

What horrendous wording. Might edit it to make it better or change some numbers around

Seal of Insanity |
Enchantment {U}
Sacrifice Seal of Insanity: Target player puts the top seven cards of their library into their graveyard.

Global Prosperity -
Enchantment
All permanents have ": Add one mana of any color to your mana pool."
Even in a world of complete abundance, the ruler is the one with the most.

Wizards Duel
Enchantment
Players may cast nonland cards as though they had flash.
Whenever a player casts a spell they may counter target spell with a lower converted mana cost.
Never bring a kobold to a dragon fight.

Web of Siken Cords
Enchantment
Auras have "you control enchanted permanent".
Decadence is its own prison. To have tasted ambrosia is to be bound to those who provide it.

Bound Fate
Enchantment
Cumulative upkeep - Pay 1 life.
Whenever a player loses life, each other player loses that much life.

Sorrow
Enchantment
Whenever a creature dies, each player loses 1 life.

cato: Interesting, but underpowered.

JadeCryptWish: I feel like this effect has been done before, and it's not that exciting anyways

Tevish Szat: For 1 mana this is insanely OP

Mown: I thought this card put the enchantment in your hand. After re-reading it, I came to the sad conclusion that your card is insanely too good

Van: This card is too complicated and has memory issues because it doesn't use counters. The wording also doesn't work

Yarium: This card is cool but I don't see why you would make it a seal. I mean, I guess it disrupts library organization. Caldera42 also pointed out that it would be really good in a Rethether combo deck. Cool!

Ogre: This card is ballin

Dudibus: The effect of this card is cool I guess, but the effect it would have on an actual game of magic is just annoying everyone.

YingLung: I think this is cool. It's debatably undercosted. "I would rather it cost 5" - Caldera42

Phoenix Toph: Whenever anyone loses life, everyone dies. Nice.

zsd: This effect is moderately cool I guess. If my contest had a top 3, you would have placed in it.

Winners: Ogre and YingLung

You power people are so boring.

just make your cards balanced

Oh no, I would nominate this, but it's too late.

nominate it for next week its fine

But it's just adding a little to the mana cost. It's such an insignificant part of the card's identity.
Not to mention that I obviously disagree with the assessment, otherwise I wouldn't submit it, but that's an aside.

Balance is an important part of card design though. Mana cost is just as important an element as anything else.

Actually discussions of what makes a good card and considerations for card design in general could be a pretty good thread.

Well, yes, I agree that mana cost is important. However, for the purpose of controlling the power level of the card, it's not really all that interesting. There are some corner cases where the cost of the card is vitally important, but in a lot of cases, it's just the means to control accessibility and efficiency. And at that point, it's for the most part entirely context dependent. Whether you want to push X theme, want it as a limited uncommon, want it as a roleplayer in standard, want to demote the use of some strategy, all of those things that needs a razorborne-lengthy essay to be explained, not a single card.

Too many people just tell you if a card is too powerful or not powerful enough, when that's something you're better off learning by just playing the game.