Master of Tragedies
Creature - Human Artist (R)
Whenever another creature dies alone, you draw a card. (A creature died alone if no other creatures died at the same time.)
"Ruman muttered his last words, but there was no one to hear him."
—The Tale of Ruman Lightbringer
2/1

Bow Before Me
Enchantment (R)
Whenever a creature enters the battlefield, tap each creature with lesser power.
"The Nayans may worship heathen gods, but they sure do know how to bow."
—Bartok the Sigiled

Proportional Response
Instant (U)
Destroy target tapped nonland permanent.

Inspired by a discussion in another thread.

Drasus, Protector of the Quarter
Legendary Creature - Human Soldier (R)
Double strike
"The rest of Akros looks down on us, but here in the Foreigner's Quarter, we're a symbol of hope. I have Kytheon to thank for that."
1/1

Serve with the Dead
Sorcery (U)
As an additional cost to cast this spell, sacrifice a creature.
Create three 1/1 white and black Spirit creature tokens with flying.

I had an idea of how to revisit this concept in a more printable way. Same flavor with less of the feel-bad of opening a legendary rare Walking Corpse.

Liliana, Cruel Mistress
Legendary Planeswalker - Liliana (M)
: If you don't control a creature named Thalia Lost, create Thalia Lost, a 2/2 legendary black Zombie creature token.
: Each player sacrifices a creature.
: Destroy all creatures, then create a 2/2 black Zombie creature token for each creature destroyed this way.


Now you can still open a legendary Walking Corpse, but it'll be in the token slot!

You know how hard it is to get to 7 loyalty counters with that +1 ability, right?

I mean, you can still activate it if you already have the token. You'll pay the "cost" of adding a loyalty counter, and then the ability will resolve and do nothing. It could maybe be lower, but I wanted to play it safe, since she's only three mana and can block something every turn with her +1. She's no Liliana, the Last Hope, but that card is very very good.

Stick Together
Enchantment (R)
At the beginning of your end step, you may return target creature card with converted mana cost X or less from your graveyard to the battlefield, where X is the number of creatures you control.
"Get back up, soldier. We're here for you."
—Rafiq of the Many

Staff of the Amesha
Artifact (R)
As long as Staff of the Amesha is untapped, creatures you control get +1/+1.
: Target creature gets +1/+1 until end of turn for each creature you control.

I don't know how printable/fun/powerful this mechanic is, but it really intrigues me. Inspired by Mata Hari's checkbox mechanic.

Information Leak
Crossroads Instant (U)
(As you play your first crossroads card each game, commit to freedom or unity for the rest of the game.)
Freedom: Scry 2, then draw a card.
Unity: Counter target spell unless its controller pays .

Hills of Possibility
Crossroads Land (R)
(As you play your first crossroads card each game, commit to freedom or unity for the rest of the game.)
Freedom: : Add one mana of any type that a land an opponent controls could produce.
Unity: : Add one mana of any type that a land you control could produce.

Viashino Blademaster
Crossroads Creature - Viashino Soldier (C)
(As you play your first crossroads card each game, commit to freedom or unity for the rest of the game.)
Freedom: Menace
Unity: First strike
2/1

Not sure what the best way is to handle things entering the battlefield without being cast, but ¯\_(ツ)_/¯. Also, you could have a token to help you remember which side you chose. (Similar in function to the City's Blessing token.)

Did people like the Citadel Siege cycle? I feel like in constructed you generally have a plan about what you want the card to do when you put it in your deck and then it just feels like extra text. It might be cool if it was a mechanic that only showed up at lower rarities. That way you are more likely to choose based on your current hand and not make the planned choice based on important cards that you want to play later. You could say that you should do that anyway because the important cards are good in either form but if they are too similar then what's the point?

I think it would definitely be a big balance challenge to make it a meaningful decision each game. In an ideal world, I imagine a deck being able to switch modes each game. Maybe they pick freedom to be a bit more aggressive and unity to be a bit more controlling.

Even for decks that always use a certain side, it could be an interesting deckbuilding restriction for standard/limited. If you really want to use the freedom side of a certain card, you can't play any crossroads cards for their unity side.

Maybe this mechanic has more feel-bad moments than it's worth, but I still feel like it has potential to be really cool.

Feed the Flames
Instant (C)
Feed the Flames deals 1 damage to any target. Add .

Stumble
Instant (U)
Target creature gets -3/-X until end of turn.
Draw a card.
On Zendikar, losing your footing often means losing your life.

Bend Fate
Sorcery (U)
Look at the top card of your library. You may put that card into your hand. If you don't, put it into your graveyard and draw two cards.

Underworld Smuggler
Creature - Human Rogue (M)
: Return Underworld Smuggler and target creature card other than Underworld Smuggler from your graveyard to your hand. Activate this ability only any time you could cast a sorcery (and only if Underworld Smuggler is in your graveyard).
"We're almost there now. Don't look back."
2/2

Banquet of Blood
Sorcery (R)
Choose target player. Each of that player's opponents gains X life, then that player loses life equal to the life gained this way.
"Not many vampire lords invite neonates to their parties, but I personally find their unadulterated bloodlust inspiring."
—Olivia Voldaren

Experimental Combat
Instant (U)
Choose one or both —
• Switch target creature's power and toughness until end of turn.
• Target creature you control fights target creature you don't control.
"Commence test 547c: octopus arms vs. jellyfish legs."
—Gulistan, Simic biomancer

Really dumb idea that's been bouncing around my head.

Go Away
Instant
Target creature leaves the battlefield.

Bolt
Instant
Bolt deals damage.

Live
Instant
You gain life.

Don't ask me what these would actually do when you played them. I have no idea.