Does it have converted mana cost 3 or more?
Burrenton Forge-Tender

19. Yes, it is blue, black, or red.
18. Yes, it is extended-legal.
17. Yes, it's monocolored.
16. Yes, it's standard-legal.
15. Yes, it's a creature.
14. No, it's not in the Alara block.
13. Yes, it's common or uncommon.
12. No, its power isn't higher than its toughness.
11. Yes, it does contain non-keyword rules text.
10. No, it has not been printed more than once.
9. No, it does not have a converted mana cost of 3 or more.

Cards that don't quite exist:
[No guess]
Consign to Dream
Thought Hemorrhage
Oona's Blackguard
Flame Jab
Master of Etherium
Knollspine Dragon
Leaf Gilder
Air Elemental
Kinscaer Harpoonist
Burrenton Forge-Tender

Is it tribally-significant, i.e. does it mention one or more creature types as a part of the card's mechanics and/or keywords?
Note: This has nothing to do with having a creature type, no matter how significant (Elf, Faerie...) that type might be.
Nectar Faerie

EDIT: Picks, power<=thoughness.

Is it black?
[strikethrough]Adder-Staff Boggart[/strikethrough]

Edit: Leaf Guilder!?!?
But since you have alerted me:
Amoeboid Changeling

8 points for Picks-at-Flies with Amoeboid Changeling. You're now at the top of the board. I was hoping someone would have asked something like "is it a Merfolk?", because the tricksy part didn't take any effect here.

Picks-at-Flies - 37
Fafnir - 32
ALEX Ryugami - 18
Ulxiz - 14
Aurora Illumina - 9
innuendo - 6
Idle Muse - 6
emperorkingx - 2

Your go.

Yeesh, that was completely random success. I have to thank Fafnir for poking me about my first guess.
Okay, the first person to post gets 3 questions and two guesses, the next 2 questions and three guesses. I just want to speed up those initial questions that get so repetitive.

Is it red, green, or white?
Living Artifact

Is it a permanent?
Balancing Act

Is it in an extended-legal set?

20. It is red, green or white.
19. It is a permanent.
18. It is in an extended-legal set.

Fallen in the water:
Living Artifact
Balancing Act

(Remember next person - 2 questions, 3 guesses)

Is it Standard-legal?
[card]Dauntless Escort

Is it multicolored?
[card]Rune-Tail, Kitsune Ascendant

Paladin en-Vec

20. It is red, green or white.
19. It is a permanent.
18. It is in an extended-legal set.
17. It is standard-legal.
16. It is multicoloured.

Invisible:
Living Artifact
Balancing Act
Dauntless Escort
Rune-Tail, Kitsune Ascendant
Paladin en-Vec

Is it common or uncommon?
Chameleon Colossus

*cough* ALEX, multicolored. *cough*

Since I can't edit my post, change my guess into Cerodon Yearling .

20. It is red, green or white.
19. It is a permanent.
18. It is in an extended-legal set.
17. It is standard-legal.
16. It is multicoloured.
15. It is not common or uncommon.

In deep slumber:
Living Artifact
Balancing Act
Dauntless Escort
Rune-Tail, Kitsune Ascendant
Paladin en-Vec
Cerodon Yearling

Is it printed at Alara Block (Shards of Alara, Conflux, or Alara Reborn)? Maelstorm Nexus .

20. It is red, green or white.
19. It is a permanent.
18. It is in an extended-legal set.
17. It is standard-legal.
16. It is multicoloured.
15. It is not common or uncommon.
14. It is in the Alara block

Concealed beneath her skirt:
Living Artifact
Balancing Act
Dauntless Escort
Rune-Tail, Kitsune Ascendant
Paladin en-Vec
Cerodon Yearling
Maelstorm Nexus

Is it a creature?
Mayael the Anima

20. It is red, green or white.
19. It is a permanent.
18. It is in an extended-legal set.
17. It is standard-legal.
16. It is multicoloured.
15. It is not common or uncommon.
14. It is in the Alara block.
13. It is a creature. <--- would have been white but it was a bit difficult to see.

Missed it:
Living Artifact
Balancing Act
Dauntless Escort
Rune-Tail, Kitsune Ascendant
Paladin en-Vec
Cerodon Yearling
Maelstorm Nexus
Mayael the Anima

Is it printed at Shards of Alara or Conflux?
[card]Karrtush, Tyrant of Jund[/card]

Is it blue or black?
Spellbound Dragon

20. It is red, green or white.
19. It is a permanent.
18. It is in an extended-legal set.
17. It is standard-legal.
16. It is multicoloured.
15. It is not common or uncommon.
14. It is in the Alara block.
13. It is a creature.
12. It is from Shards of Alara or Conflux
11. It is blue or black.

Losing the faith:
Living Artifact
Balancing Act
Dauntless Escort
Rune-Tail, Kitsune Ascendant
Paladin en-Vec
Cerodon Yearling
Maelstorm Nexus
Mayael the Anima
Karrthus, Tyrant of Jund
Spellbound Dragon

Is it a legendary creature?
Maelstrom Archangel

20. It is red, green or white.
19. It is a permanent.
18. It is in an extended-legal set.
17. It is standard-legal.
16. It is multicoloured.
15. It is not common or uncommon.
14. It is in the Alara block.
13. It is a creature.
12. It is from Shards of Alara or Conflux
11. It is blue or black.
10. It is not a legendary creature.

Getting on down:
Living Artifact
Balancing Act
Dauntless Escort
Rune-Tail, Kitsune Ascendant
Paladin en-Vec
Cerodon Yearling
Maelstorm Nexus
Mayael the Anima
Karrthus, Tyrant of Jund
Spellbound Dragon
Maelstrom Archangel

Is it artifact creature?
Magister Sphinx

20. It is red, green or white.
19. It is a permanent.
18. It is in an extended-legal set.
17. It is standard-legal.
16. It is multicoloured.
15. It is not common or uncommon.
14. It is in the Alara block.
13. It is a creature.
12. It is from Shards of Alara or Conflux
11. It is blue or black.
10. It is not a legendary creature.
9. It is not an artifact creature.

In the other place:
Living Artifact
Balancing Act
Dauntless Escort
Rune-Tail, Kitsune Ascendant
Paladin en-Vec
Cerodon Yearling
Maelstorm Nexus
Mayael the Anima
Karrthus, Tyrant of Jund
Spellbound Dragon
Maelstrom Archangel
Magister Sphinx

Is it exactly two colors?
Giltspire Avenger

20. It is red, green or white.
19. It is a permanent.
18. It is in an extended-legal set.
17. It is standard-legal.
16. It is multicoloured.
15. It is not common or uncommon.
14. It is in the Alara block.
13. It is a creature.
12. It is from Shards of Alara or Conflux
11. It is blue or black.
10. It is not a legendary creature.
9. It is not an artifact creature.
8. It is not exactly two colours.

Stolen away:
Living Artifact
Balancing Act
Dauntless Escort
Rune-Tail, Kitsune Ascendant
Paladin en-Vec
Cerodon Yearling
Maelstorm Nexus
Mayael the Anima
Karrthus, Tyrant of Jund
Spellbound Dragon
Maelstrom Archangel
Magister Sphinx
Giltspire Avenger

I'm sure you lot are posting one at a time to make me think of more ancient songs.

Is the converted mana cost 7 or more?
Sedraxis Specter

Does it have flying?
Empyrial Archangel

20. It is red, green or white.
19. It is a permanent.
18. It is in an extended-legal set.
17. It is standard-legal.
16. It is multicoloured.
15. It is not common or uncommon.
14. It is in the Alara block.
13. It is a creature.
12. It is from Shards of Alara or Conflux
11. It is blue or black.
10. It is not a legendary creature.
9. It is not an artifact creature.
8. It is not exactly two colours.
7. It does have a converted mana cost of 7 or more.
6. It does not have flying.

Baby:
Living Artifact
Balancing Act
Dauntless Escort
Rune-Tail, Kitsune Ascendant
Paladin en-Vec
Cerodon Yearling
Maelstorm Nexus
Mayael the Anima
Karrthus, Tyrant of Jund
Spellbound Dragon
Maelstrom Archangel
Magister Sphinx
Giltspire Avenger
Sedraxis Spectre
Empyrial Archangel

Is it Charnelhoard Wurm?
Prince of Thralls

Is it Hellkite Overlord?
Blood Tyrant

@Fafnir: Doesn't have flying...

It does.

Indeed, reading is tech. But I'll echo Aurora; it doesn't have flying.

Green text doesn't always mean yes.
And red text doesn't always mean no either.

Whoops, double read fail.
Charnelhoard Wurm... last edit >_> Sorry.

Is it mythic rare?
Charnelhoard Wurm

I'm going to have to give this to Fafnir, for 4 points. Only fair since he gave me my last win.

It is indeed Charnelhoard Wurm. No particular story to tell on this one (other than you should kill it immediately), just one of Aurora's random cards.

All yours, Fafnir.

Picks-at-Flies - 37
Fafnir - 36
ALEX Ryugami - 18
Ulxiz - 14
Aurora Illumina - 9
innuendo - 6
Idle Muse - 6
emperorkingx - 2

I should point out that Fafnir is the only one to have defeated us so far.

...And I've helped Fafnir on this one. Proofreading is tech.

(I haven't defeated anyone on MTGS yet, but I have caused someone to get 1 point before. I won't say what it is, because I may do that one here later.)

Poor me that couldn't see edited posts by e-mail .

Yep, that's what happens when you are sleep-deprived and start posting at high speed because you have to nail the right card before anyone else. You misread stuff and end up looking like an idiot.

Thanks for the help, though. Especially it would have likely - and did - cost you the win. I'll remember that.

Going to sleep now and be back in the morning. But before I go, there's one last I have to ask.

... which card I'm thinking of?

P.S.: 3/2 and 2/3 rule for the first two posts, as done in the last challenge, to speed the game up.

That's because you posted Blood Tyrant at that time and I didn't thought you would edit that.

Is it white, blue, or black?
Brainstorm

Is it Extended-Legal?
Flameblast Dragon

Is it common or rare?

20. It is , or .
19. It's not Extended legal.
18. It's neither common nor rare.

Wrong guesses:
Brainstorm
Flameblast Dragon

Ordered Migration

Is it a permanent?
Spell Counter

Does it have a converted mana cost of 4 or greater?
Cabal Therapy

Is it at Un-set?
[card]To Arms![/card]

20. It is , or .
19. It's not Extended legal.
18. It's neither common nor rare.
17. It isn't a permanent.
16. It does have a CMC of 4 or more.
15. It isn't in a Un-set.

Wrong guesses:
Brainstorm
Flameblast Dragon
Ordered Migration
Spell Counter
Cabal Therapy
To Arms!

How stupid I am, guessed with with a T.1X legal card. XD
Is it multicolored?
Icatian Town

20. , or .
19. Not Extended legal.
18. Neither common nor rare.
17. Not a permanent.
16. Its CMC is 4 or more.
15. It isn't in a Un-set.
14. Not multicolored.

Wrong guesses:
Brainstorm
Flameblast Dragon
Ordered Migration
Spell Counter
Cabal Therapy
To Arms!
Icatian Town

Is it black?
Amnesia