The sixteen competitors have submitted the cards that they want R&D to make if they win. We'll post who submitted which card later, but first, try to guess!
Creature - Angel
Sacrifice <designer>'s Angel, Choose and discard a white card: Destroy target artifact or enchantment.
Creature - Elf
Sacrifice a creature: Destroy target artifact or enchantment. Put a 2/2 green <designer> token into play under control of the destroyed card's controller.
All creature's text boxes are blank. If a creature's power or toughness is undefined, treat it as 0.
Whenever enchanted creature attacks, target creature blocks enchanted creature if able. Whenever enchanted creature is blocked, you may return Elvish Tracking to owner's hand.
You may sacrifice a swamp and a mountain instead of paying Firebolt's casting cost.
Firebolt deals 3 damage to target creature or 2 damage to target player.
Creature - Goblin
When Goblin Gravedigger comes into play, return a mountain to you hand or sacrifice Goblin Gravedigger.
Goblin Gravedigger gains +1/+2 if there is another goblin in play.
"He's not so eager to dig when he's the only one on the battlefield."
Hand of <designer>
As you play Hand of <designer>, choose and discard a card from your hand. Gain control of target permanent.
"It just disappeared into the sky . . . I swear."
Creature - <creature type>
You may play <designer>'s Man-o'War anytime you could play an instant.
When <designer>'s Man-o'War comes into play, return target creature to owner's hand.
Look at the top two cards of your library. Put one in your hand and the other on the bottom of your library. Then look at the top X cards of your library. Put one in your hand and the rest on the bottom of your library.
Creature - Wizards of the Coast
As The Meddler comes into play, name a card.
Sacrifice The Meddler: Counter named card.
As Miser's Fountain come into play, pay 5 or less life. For each life paid in this way, choose a color.
T: Add 1 to your mana pool.
T: Add one mana of any of the chosen color(s) to your mana pool.
T: Add 1 to your mana pool
1W, T: Target creature gains First Strike until end of turn.
1U,T: Target creature gains Flying until end of turn.
1B,T: Target creature cannot be blocked by non-black, non-artifact creatures until end of turn.
1R,T: Target creature gains Haste until end of turn.
1G,T: Regenerate target creature.
2,T: Choose a color. Target creature is the chosen color until end of turn.
Whenever a card comes into play, other than from a player's hand, remove it from the game instead. Whenever a card enters a players hand, other than from play, remove it from the game unless it was the first card that player drew during their draw step
If you control a plains and an opponent controls a non-basic land, you may play Simplify without paying its casting cost. Destroy target artifact or enchantment.
Wall of Mirrors
Creature - Wall
T: Look at the top card of target player's library.
1U,T: Name a card. Put the top card from target opponent's library into his or her graveyard. If that card is the one named, draw a card.
Creature - Wall
All opponents play with with their hands face up.
1U, Sacrifice Wizards's Watchtower: Draw a card.