Make your own card!!!

[Demigoron]

Silvinra, The All-seeing Eye {B}{B}{U}{U}{3}
Legendary Dragon- counselmember
flying
{U}{U}{3}: look at the top 3 cards of target opponents library and put each on the top or bottom.  For each card put on the top, draw a card
{B}{B}{3}: chose one-each opponent discards two cards or sacrifices two permanents; either way, each opponent draw a card
5/5
"The Dark Counsel knows what you will do before you do.  What could posssibly defeat such power?"

[Demigoron]

Intrepnia, Master Scientist  {R}{R}{U}{U}{3}
Legendary dragon- counselmember
flying
{U}{U}{3}: copy two instants or sorceries cast this turn, you may choose new tagets for the copies
{R}{R}{3}: target creature does damage to itself equal to its CMC and to its controller equal to half its power plus its toughness
5/5
"This has the potential to be quite spectacular, if it works."
"It also has the potential to be quite dangerous."
"Only to your precious humans, the Dark Counsel does not fear my experiments."
Intrepnia, to Esplin.

[Demigoron]

Casronor, Bringer of Chaos  {B}{B}{R}{R}{3}
Legendary Dragon- counselmember
flying
{B}{B}{3}: If a permanent is sacrified this turn it is not.  Instead, its owner placs a copy of that permanent onto the battlefield under their control.  Cards discarded this turn may be cast without paying their mana costs.
{R}{R}{3}: choose 5 permanents on the battlefield randomly.  Randomly decide heads or tails, then flip a coin for each permanent chosen. Permanents whose coins land on the chosen side are sacrificed.  Each player then discards 2 cards.
5/5
"I like chaos, and as long as the Dark Counsel rules I can create  as much of it as I want."

[Demigoron]

Gonlel, The Recycler  {G}{G}{B}{B}{3}
Legendary Dragon- counselmember
flying
{G}{G}{3}-add one mana of any color to your mana pool for each creature or land in a graveyard
{B}{B}{3}-exile a card from a graveyard.  You may cast it this turn.  If you don't, gain life equal to its power or toughness, whichever is greater.
Everytime a card enters an opponents graveyard, you may have them lose a life.
5/5
"Waste!  How do you expect the Dark Counsel to keep everything running smoothly if humans are running amok, using everything in sight?

[Demigoron]

Banfeild, He Who Smashes  {G}{G}{R}{R}{3}
Legendary Dragon- Counselmember
flying
{R}{R}{3}: Up to two target creatures gain first strike, haste, and +2/+0 until end of turn.
{G}{G}{3}: Up to 2 target creatures get +3/+3 until end of turn.  Regenerate each creature you control.
5/5
"Humans are fun to smash, but Dragons are ever funnier.  And with the Dark Counsel in control, I can smash everything I want!"

[Demigoron]

Arcren, Leader of Legions  {R}{R}{W}{W}{3}
Legendary Dragon- Counselmember
Flying
{R}{R}{3}: Creatures you control gain first strike and vigilence until end of turn.
{W}{W}{3}:  Creatures you control gain +2/+2 until end of turn
5/5
""Even the Dark Counsel fears my armies, that's why they let me lead theirs."

[FlickerYourOwnIdentity]

Yeah, {Berserk} words it well. "Target creature gets +X/+0 and trample, where X is its power. At the beginning of the end step, destroy it if it attacked this turn."
Maybe you could make it each combat to target opponents creatures to deter attacks or target blockers and not have to sac them.

I see what your saying here and I get it.  However, in order to be a balanced card, it has to have a drawback if I want to keep that low mana cost.  Even at a higher mana cost it could still very well win games.  In order to make a card (for me anyway) I make a list of things I want it to do, and possible drawbacks.  Here was my list for this card.

Want(s)
1. Low mana cost
2. Quick damage in short amount of time
3. Make creatures bigger

Possible drawback(s)
1. Exile the targeted creature at the end of the turn/at the end of combat.
2. Opponent gains life equal to the targeted creature's toughness at the end of combat.
3. Deal damage equal to creatures power to owner.
4. Must effect that only targets your creatures, and doesn't give them haste.
5. Can only target green creatures

And that's my list.  I went with the third one at first, but I realize my mistake in that, imagine {Ball Lightning} being played the next turn.  Then again that would also be a problem in general so I added that last possible drawback to the list.  Right now I have crossed off both 2. And 3. from my list, and the rest I will use.  However I am a little bit iffy on the 5th one.  Thoughts?

[Demigoron]

Lenthra, The Reduplicator  {W}{W}{G}{G}{3}
Legendary Dragon- Counselor
{G}{G}{3}:choose one: put 2 3/3 beast tokens on the battlefield; or put 2 2/2 knight tokens with vigalance on the battlefield; or put 1 5/5 elemental token with trample on the battlefield
{W}{W}{3}: For every token on the battlefield, put a token under your control on the batlefield as a copy of that token.
5/5
"Bonte thinks his homegrown armies are the most powerful force on this plane.  Let's see his forces compete with my endless armies and we'll see which the Dark Counsel should purchase."

[Demigoron]

Bonte, The strengthener  {G}{G}{U}{U}{3}
Legendary Dragon- Counselmember
Flying
{G}{G}{3}: place 3 +1/+1 counters on up to 2 target creatures.
{U}{U}{3}: Draw cards equal to target creatures power.
5/5
"Lenthra thinks her armies of wealkings can compete with my projects.  Let the Dark Counsel see the power of biotechnology as I crush them all."

[FlickerYourOwnIdentity]

Archive of Manipulation  {2}{U}{U}
Artifact

At the beginning of your upkeep, put a Mastery counter on Archive of Manipulation
At the beginning of each players' upkeep, that player taps X permanent(s), where X is equal to the number of Mastery counters on Archive of Manipulation

"Obey."

[5/9 Turtle]

Archive of Manipulation  {2}{U}{U}
Artifact

At the beginning of your upkeep, put a Mastery counter on Archive of Manipulation
At the beginning of each players' upkeep, that player taps X permanent(s), where X is equal to the number of Mastery counters on Archive of Manipulation

"Obey."

This is really nice, I like

[Kaworu, the Fifth Child]

Eren, Wild Titan    {R}{W}{G}
Planeswalker- Eren
+1: Destroy target creature with power 5 or greater.
-3: Eren becomes a 6/6 Titan creature with haste and first strike until end of turn. If he were to die, instead tap him and remove him from combat.
-9: You get an emblem that says, "Whenever a creature with power 5 or greater attacks you, if you control a Human, destroy that creature.

Loyalty: 4

[Apathy Reactor]

Eren, Wild Titan    {R}{W}{G}
+1: Destroy target creature with power 5 or greater.
-3: Eren becomes a 6/6 Titan creature with haste and first strike until end of turn. If he were to die, instead tap him and remove him from combat.
-9: You get an emblem that says, "Whenever a creature with power 5 or greater attacks you, if you control a Human, destroy that creature.

Annie, Intelligent Titan {R}{G}{B}{2}
Lgendary Creature - Titan
{B} destroy target creature with toughness 1
{G}{G}Annie, Intelligent Titan gains +3 toughness and hexproof until the end of the turn
{R}{R}{R}{T} destroy target artifact or non-basic land

[Destore117]

Eren, Wild Titan    {R}{W}{G}
+1: Destroy target creature with power 5 or greater.
-3: Eren becomes a 6/6 Titan creature with haste and first strike until end of turn. If he were to die, instead tap him and remove him from combat.
-9: You get an emblem that says, "Whenever a creature with power 5 or greater attacks you, if you control a Human, destroy that creature.

Types rarity starting loyalty?

[Kaworu, the Fifth Child]

Eren, Wild Titan    {R}{W}{G}
+1: Destroy target creature with power 5 or greater.
-3: Eren becomes a 6/6 Titan creature with haste and first strike until end of turn. If he were to die, instead tap him and remove him from combat.
-9: You get an emblem that says, "Whenever a creature with power 5 or greater attacks you, if you control a Human, destroy that creature.

Annie, Intelligent Titan {R}{G}{B}{2}
Lgendary Creature - Titan
{B} destroy target creature with toughness 1
{G}{G}Annie, Intelligent Titan gains +3 toughness and hexproof until the end of the turn
{R}{R}{R}{T} destroy target artifact or non-basic land

Female titan yo, there's 5 shifters.