Ru says "Sacrifice that you might gain great power!"

Ru's Minotaur
Creature - Minotaur
You may have ~ enter the battlefield with a -1/-1 counter on it.
~ has haste as long as it has a -1/-1 counter on it.
4/3

Ru's Tengu
Creature - Bird
You may have ~ enter the battlefield with a -1/-1 counter on it.
~ has flying as long as it has a -1/-1 counter on it.
3/2

Ru's Naga
Creature - Naga
You may have ~ enter the battlefield with a -1/-1 counter on it.
~ has deathtouch as long as it has a -1/-1 counter on it.
2/2

Ru's Mummy
Creature - Zombie
You may have ~ enter the battlefield with a -1/-1 counter on it.
~ has menace as long as it has a -1/-1 counter on it.
5/3

Ru's Vampire
Creature - Vampire
You may have ~ enter the battlefield with a -1/-1 counter on it.
~ has lifelink as long as it has a -1/-1 counter on it.
5/5

Aethermancer
Creature - Human Wizard
Flash
When ~ enters the battlefield, each player returns a non-wizard creature they control to its owner's hand.
2/2

Shadow Puppets
Instant
For each creature you don't control that's attacking or blocking, create a token that's a copy of it.

Aethermancer\s nonwizard clause is a nice way off disallowing it to repeat its ability ad nauseum. Useful for abusing etb effects or as a tempo play in an all wizard deck. I feel that bounce has gotten a lot weaker over the last few years though as etb triggers start carrying more weight.

Shadow Puppets is fun. It seems like one of those designs that has to have been done before, but I can't think of where. MEchanically, it doesn't feel black. Straight blue would work, but I think would be best. It would need reflavouring though. They're reflections maybe? Or you're making them fight their better nature?

I think you should keyword the -1/-1 counter ability as "leash."

Aethermancer is neat.

Alissa's Handiwork
Instant
Destroy target creature. Its controller creates a colorless artifact token named Gold. It has "Sacrifice this artifact: Add one mana of any color to your mana pool."
The Baron was found dead in his chamber, his throat slit, and in his mouth, a single gold coin.

Cryptic Tutor
Sorcery
Target opponent names a card. Search your library for a card with a different name, reveal it, and put it into your hand. Then, shuffle your library.
She teaches the lessons you need to know, not the ones you want to.

Exhaustive Study
Sorcery
Search your library for a card, put it into your hand, then shuffle your library.
Suspend 4--

Nova, the Enlightened
Legendary Planeswalker - Nova
{+2} Exile the top three cards of your library. You may play one of them this turn.
{-2} Untap target creature and gain control of it until your next turn. It gains vigilance and haste until your next turn.
{-10} Until end of turn, you may play cards exiled with ~ without paying their mana cost.
{4}

Mage's Staff
Artifact
, : ~ deals 1 damage to target creature or player.
I know it's strictly better than Rod of Ruin. I just don't care.

Hunter's Bow
Artifact
, : ~ deals 2 damage to target player.

Paladin's Summons
Artifact
, : Create a 1/1 white soldier creature token.
Yes, I know it's strictly better than Nuisance Engine. I don't care.

Warlock's Skull
Artifact
, : You draw a card and lose 2 life.

Priest's Relic
Artifact
, : Choose one:
-Prevent the next 2 damage that would be dealt to target creature or player this turn.
-You gain 2 life.

So my Main Dude i talk about Magic with—the one who first really got me into the game in 8th grade 13 years ago about a month before Guildpact, whom i go to prereleases with and who always makes the top 4 while i don't walk away with any prizes, etc.—is through-and-through a 95% Spike, 5% Johnny, "Draw-go decks were the peak of Magic, i'm still bitter they voted in Rewind over Dismiss, Lorwyn (Cryptic Command) and Kamigawa (Mana Leak) are the two most underrated blocks of all time, Surveil is the coolest mechanic they've previewed since Innistrad, and if they reprinted Duress then why can't they reprint Counterspell" kinda guy

and i was showing him some cards from these boards that really blew me away, namely the Planeswalker round from the Pro Tour, and he was thoroughly unimpressed

so i said "hold on, i know just the designer for you. lemme dig up his card dump"

linked him to the most recent post

and when he read back to Cryptic Tutor, he said:

"yeah this is the good **** lol"

so thanks for giving me something to show off from these boards that even the most hardline control deck fundamentalist I've ever met in my life could appreciate.

Congratulations, you've found my target demographic.

And now, some cards:

Lady in Green
Creature - Human
When ~ dies, put a +1/+1 counter on target creature you control.
1/1
When stricken down by swordstroke lethal,
she left her kin a small bequeathal.

Lady in Red
Creature - Human
Whenever ~ deals combat damage to a player, discard a card. If you do, draw a card.
1/1
Color of wine, fire, blood, and treason,
all things beyond conscience and reason.

Lady in Black
Creature - Human
Deathtouch
1/1
No matter her crimes, she has no contrition,
no matter her station, there's always ambition.

Lady in Blue
Creature - Human
When ~ enters the battlefield, scry 2.
1/1
Knowledge brings profit, power, and health,
she seeks it only for itself.

Lady in White
Creature - Human
Whenever ~ attacks or blocks, other creatures you control get +0/+1 until end of turn.
1/1
To be a sage, a lord or wife,
none can compare to saving life.

Gravemaker Edward
Legendary Creature - Human
When ~ enters the battlefield, put a grave counter on target creature you don't control.
As long as a creature has a grave counter on it, ~ gets +0/+13 and has deathtouch.
3/1

Godsworn Abraham
Legendary Creature - Human Cleric
Vigilance
: ~ deals damage to target creature equal to the damage it has dealt this turn.
5/5

Collector Daniel
Legendary Creature - Human Advisor
When ~ enters the battlefield, gain control of target creature for as long as you control ~.
At the beginning of your upkeep, that creature fights ~.
0/7

Snaresetter Rachel
Legendary Creature - Human Rogue
~ enters the battlefield with 2 trap counters on it.
Remove a trap counter from ~: Search your library for a trap card, reveal it, and put it into your hand, then shuffle your library.
2/2

Lifetaker Isaac
Legendary Creature - Human Barbarian
~ attacks each turn if able.
Whenever ~ attacks a player untap target creature that player controls with the lowest power among creatures that player controls. That creature blocks ~ this turn if able.
4/3

Cellminder Catherine
Legendary Creature - Human Advisor
Whenever ~ blocks or becomes blocked by one or more creatures, exile one of them.
When ~ dies, target opponent puts a 2/2 black zombie creature token onto the battlefield for each creature exiled with ~.
4/4

Permanent Revolution
Enchantment
Whenever a creature with the greatest power or tied for the greatest power among creatures in play attacks or blocks, you may pay . If you do, ~ deals X damage to that creature.
Liberty is not a passive state of affairs, but a continuous state of affairs, with each new tyrant that rises going down in flames.

Gluttonous Lurker
Creature - Horror (U)
Flash
Morbid - ~ enters the battlefield with two +1/+1 counters on it if a creature died this turn.
3/4
"Its mouth is lined with row upon row of teeth, each as long as yer head, and every one of them pressed into a smile."
-Yari, Gatstaf taleteller

Agitative Propaganda
Enchantment
Creatures your opponents control have "this creature attacks each turn if able unless you pay ".
Dulce et decorum est pro patria mori.

The First Level
Enchantment
Whenever a creature dies, you may sacrifice ~. If you do, destroy target creature.
Witnessing death doesn't end with watching.

The Second Level
Enchantment
Whenever a creature attacks and isn't blocked, you may sacrifice ~. If you do, ~ deals 4 damage to target creature or player.
There's no outrunning him.

The Third Level
Enchantment
Whenever a creature enters the battlefield, you may sacrifice ~. If you do, exchange control of it and target creature with a different controller.
A man possessed by his possession.

The Fourth Level
Enchantment
Whenever a creature becomes blocked, you may sacrifice ~. If you do, creatures you control get +X/+X until end of turn, where X is that creature's power.
Be his, or be his enemy.

The Fifth Level
Enchantment
Whenever one or more creatures attack, you may sacrifice ~. If you do, exile all attacking creatures.
A punishment in search of a crime.

The Sixth Level
Enchantment
Whenever a card is put into an opponent's graveyard from anywhere, you may exile ~. If you do, you may cast up to two target nonland cards from that player's graveyard without paying their mana cost.
The innocent have nothing to fear.

Celestial Blessings: strongest when the stars align

Wisdom of the Moon
Instant
Draw two cards.
If each player controls an equal number of permanents, draw four cards instead.

Glow of the Sun
Instant
Creatures you control get +1/+1 until end of turn.
If you control exactly two creatures, those creatures get +2/+2 until end of turn instead.

Might of the Earth
Instant
Target creature you control fights target creature you don't control.
If those creatures have the same power, the creature you control gains indestructible until end of turn.

Fires of Mars
Instant
~ deals 3 damage to target creature. If that creature has toughness 3, ~ deals that much damage to that creature's controller.

Pull of the Void
Sorcery
Target player discards two cards. If those cards share a converted mana cost, that player discards two more cards.

Very syzygistic.

Some characters:

Ruthless Mastermind
Legendary Creature - Human Advisor
: Target creature you control gains deathtouch until end of turn and fights target creature.
4/4

Dogged Investigator
Legendary Creature - Human Soldier
Whenever a creature an opponent controls without a crime counter on it deals damage, put a crime counter on it.
: Exile target creature with a crime counter on it.
4/4
"Why can't I catch him? I can find his pawns, but he keeps getting away!"

Some D&D classes

Party Paladin
Creature - Human Soldier Cleric
Whenever ~ attacks or blocks, prevent the next 3 damage that would be dealt to another target creature or player this turn.
3/4

Party Rogue
Creature - Human Rogue
~ can't be blocked.
Whenever ~ deals combat damage to a player, tap target artifact that player controls. It doesn't untap during its controller's next untap step.
1/1

Party Wizard
Creature - Human Wizard
When ~ enters the battlefield, exile the top 5 cards of your library face down.
: You may cast an instant or sorcery card exiled with ~.
2/2

Party Bard
Creature - Human Wizard Rogue
Prowess
: Another target creature gets +X/+X until end of turn, where X is ~'s power.
1/3

Party Druid
Creature Human Druid
: Add to your mana pool. If this mana is spent to cast a creature spell, that creature enters the battlefield with a +1/+1 counter on it.
2/4

Party Sorcerer
Creature - Human Wizard
Whenever a spell you control deals damage to one or more permanents or players, draw a card.
3/1

Party Warlock
Creature - Human Cleric
When ~ enters the battlefield, you may reveal a creature card from your hand. Target creature gets -X/-X until end of turn, where X is the revealed card's power.
2/4

Party Fighter
Creature - Human Soldier
Double Strike
When ~ enters the battlefield, you may attach target equipment you control to ~.
3/2

Party Barbarian
Creature - Human Barbarian
~ enters the battlefield with a rage counter on it.
Remove a rage counter from ~: ~ gets +2/+2 until end of turn.
2/2

Party Cleric
Creature - Human Cleric
Lifelink
: ~ deals 1 damage to target player.
, , Pay 8 life: Return target creature card from your graveyard to the battlefield.
2/4

An adventuring party:

Alrec, the Scion
Legendary Creature - Human Warrior
Haste
Whenever ~ attacks, choose a number. ~ can't be blocked by exactly that many creatures this turn.
"I shall sign my name in the book of history, and I shall sign it in fire!"
4/4

Insara, the Protector
Legendary Creature - Human Knight
Whenever a creature an opponent controls attacks or blocks, you may have ~ fight that creature.
"Those who draw their swords against the helpless will instead find them crossed with mine."
3/5

Thomas, the Dark Mage
Legendary Creature - Human Wizard
When ~ enters the battlefield, reveal the top 5 cards of your library. Put two of them into your hand, and you lose life equal to their converted mana costs, and put the rest into your graveyard.
"Power has a price. So, too, does powerlessness."
2/3

Grey, the Godly
Legendary Creature - Human Cleric
If a source would deal damage to a permanent you control, it deals that much damage minus 1 instead, and its controller loses 1 life.
"Somebody said, from the bible he'd quote
There was dust on the man in the long black coat."
-Robert Zimmerman
4/4

Elissa, the Pact-Bound
Legendary Creature - Human Wizard
When ~ enters the battlefield, search your library for a creature card, exile it, then shuffle your library.
Sacrifice ~: you may cast the exiled card (You still pay its mana cost)
"In life, I wield only a small part of its power, but in death, I shall become its power."
3/3

Olossia, the Wisened
Legendary Creature - Elf Druid
When ~ dies, search your library for a land card and put it onto the battlefield, then shuffle your library.
"Seasons pass, and yet the seasons never do."
4/4

Moira, the People's Voice
Legendary Creature - Human Cleric
~'s power and toughness are equal to the number of creatures you control.
When ~ dies, exile it and return to the battlefield all creature cards in your graveyard that were put there from the battlefield this turn.
*/*

Teloros, The Measured
Legendary Creature - Human Wizard
Whenever a player casts a permanent spell, that player returns a permanent they control that shares a type with it to its owner's hand.
4/4

Coronos, The Illuminator
Legendary Creature - Human Cleric
Whenever ~ attacks, target creature can't block this turn.
Whenever ~ blocks, you may remove target attacking creature from combat.
4/4

Escadia, the Intricate
Legendary Creature - Human Wizard
When ~ enters the battlefield, target opponent chooses a number from 1 to 5. Search your library for a card with that converted mana cost, reveal it, then put it into your hand and shuffle your library.
1/5

Esme, the Erratic
Legendary Creature - Human Wizard
Whenever ~ attacks, draw three cards.
Whenever ~ deals combat damage to a player, discard three cards.
4/4

Rettick, the Ragpicker
Legendary Creature - Human Nomad
When ~ enters the battlefield, you may return target card in your graveyard to your hand. If you do, you lose life equal to its converted mana cost.
4/4

Koloros, the Torturer
Legendary Creature - Human Shaman
When ~ enters the battlefield, choose target creature you don't control.
Whenever damage is dealt to a player, ~ deals that much damage to that creature.
4/4
"We cannot punish every sinner, so those we can must also pay for the crimes of those we cannot."

Ohm, the Galeforce Fist
Legendary Creature - Human Monk
Trample
Whenever ~ blocks or becomes blocked, you may return target creature blocked by or blocking it to its owner's hand.
"It is a petty power that crushes its enemies, true power simply needn't concern it self with them."
4/4

A party of novices grows up to become heroes:

Selorise, the Scholar
Legendary Creature - Human Wizard
First strike, Prowess
At the beginning of your upkeep, put an experience counter on ~. Then, if ~ has 4 or more experience counters on it, transform it.
2/1
//
Selorise, the Spellspear
Legendary Creature - Human Wizard
First Strike
Whenever you cast a noncreature spell, target creature you control gets +2/+2 until end of turn.
3/2

Alacra, the Outlaw
Legendary Creature - Human Rogue
Lifelink, Menace
At the beginning of your upkeep, put an experience counter on ~. Then, if ~ has 4 or more experience counters on it, transform it.
2/2
//
Alacra, the Outlandish
Legendary Creature - Human Rogue
Lifelink
Whenever ~ attacks, up to one target creature can't block this turn, and untap up to one target creature and it blocks ~ this turn if able.
3/3

Darnithe, the Dauntless
Legendary Creature - Human Archer
Vigilance, Reach
At the beginning of your upkeep, put an experience counter on ~. Then, if ~ has 4 or more experience counters on it, transform it.
2/3
//
Darnithe, the Deadshot
Legendary Creature - Human Archer
Vigilance
: ~ deals damage equal to its power to target attacking or blocking creature with flying.
3/4

Bellisive, the Brigand
Legendary Creature - Human Knight
Whenever ~ attacks or blocks, you lose 2 life.
At the beginning of your upkeep, put an experience counter on ~. Then, if ~ has 4 or more experience counters on it, transform it.
4/3
//
Bellisive, The Blackguard
Legendary Creature - Human Knight
Whenever ~ attacks or blocks, target opponent loses 2 life and you gain 2 life.
4/3

Henry, the Healer
Legendary Creature - Human Cleric
Creatures you control have absorb 1.
At the beginning of your upkeep, put an experience counter on ~. Then, if ~ has 4 or more experience counters on it, transform it.
2/2
//
Henry, the Holy
Legendary Creature - Human Cleric
Creatures you control have absorb 2.
Whenever damage is prevented, you gain that much life.
3/3

And, a bonus card:

Silent Spirit
Creature - Spirit
Your opponents can't cast spells while ~ is attacking or blocking.
3/3

Some ETB creatures:

Mistral Drake
Creature - Drake
Flying
When ~ enters the battlefield, target creature doesn't untap during its controller's next untap step.
2/1

Aggressive Yeti
Creature - Yeti
When ~ enters the battlefield, target creature gets +2/+0 until end of turn.
4/2

Frightful Bones
Creature - Skeleton Warrior
When ~ enters the battlefield, target creature gains menace until end of turn.
3/2

Garrison Quartermaster
Creature - Human Soldier
When ~ enters the battlefield, target creature gets +1/+1 until end of turn.
2/2

Hunting Dogs
Creature - Hound
When ~ enters the battlefield, target creature must be blocked this turn if able.
3/3