Some cards I saw in the spoiler -

Meglonoth
Creature - Beast   
Vigilance, trample
Whenever Meglonoth blocks a creature, Meglonoth deals damage equal to its power to target player.
6/6

Not horribly good, but if a stack is lacking in creatures, he seems pretty cool

Path to Exile
Instant   
Remove target creature from the game. Its controller may search his or her library for a basic land card, put it into play tapped, then shuffle his or her library.

I'm surprised nobody else has mentioned this, actually, it's targeted removal that RFGs and has no real drawback (well, barring some shuffling shenanigans)   I play STP, and I don't see much of a reason to pass this up.

EDIT:

Inkwell Leviathan

Artifact Creature - Leviathan   
Islandwalk, trample, shroud
7/11

This creature is certainly good enough, especially for those who play with *walk making creatures unblockable

I've had a type 4 stack for a while, but I never really that great of a stack, due to the lack of older cards.  However, I'm finally going to shell out some money for some of them, and I was wondering what cards (lets say, pre-Onslaught block) would you not play without?

Anyways, here's what I have currently.  I'm not sure how consistent the power level is, as I haven't played with the recently updated stack recently.  We play with suspend and evoke as freebies, and if a spell uses 0 mana, its free.

*Artifacts*

Aladdin's Ring
Crown of Convergence
Gleemax
Legacy Weapon
Mind's Eye
Mindslaver
Mirari
Mizzium Transreliquat
Nevinyrral's Disk
Null Brooch
Oblivion Stone
Planar Portal
Reito Lantern
Soul Foundry
Tatsumasa, the Dragon's Fang
Tormod's Crypt
Tower of Fortunes
Vedalken Orrey
World-Bottling Kit

*Creatures*

Aeon Chronicler
Angel of Salvation
Arashi, the Sky Asunder
Arcanis the Omnipotent
Armored Guardian
Aven Mindcensor
Azorius Guildmage
Bane of the Living
Bloodfire Colossus
Body Double
Bosh, Iron Golem
Bringer of the Black Dawn
Bringer of the Blue Dawn
Chromeshell Crab
Crowd Favorites
Darksteel Colossus
Deepfire Elemental
Descendant of Soramaro
Dimir Doppelganger
Draining Whelk
Eight-and-a-Half Tails
Ertai, Wizard Adept
Faerie Macabre
Figure of Destiny
Firemane Angel
Genesis
Glarecaster
Glory
Gorilla Shamn
Greater Morphling
Grothoth
Guile
Infernal Spawn of Infernal Spawn of Evil
Intet, the Dreamer
Iridescent Angel
Jiwari, the Earth Aflame
Jushi Apprentice
Kaervek, the Merciless
Krosan Cloudscraper
Krosan Colossus
Masticore
Memnarch
Metathran Aerostat
Mindleech Mass
Mischievous Quanar
Mistmeadow Witch
Myojin of Infinite Rage
Myojin of Cleansing Fire
Myojin of the Seeing Winds
Mystic Snake
Necrotic Sliver
Nicol Boras
Offalsnout
Panglacial Wurm <-- Playable for free from the library.
Phage the Untouchable
Plated Slagwurm
Protean Hulk
Puppeteer Clique
Quicksilver Dragon
Razia, Boros Archangel
Reya Dawnbringer
Riptide Shapeshifter
Scourge of Kher Ridges
Seht's Tiger
Siege-Gang Commander
Silklash Spider
Simic Sky Swallower
Sisters of Stone Death
Skinthinner
Slithermuse
Smokespew Invoker
Stonecloaker
Stuffy Doll
Symbiotic Wurm
Teferi, Mage of Zhalfir
Teneb, the Harvester
Uktabi Kong
Venser, Shaper Savant
Vesuvan Shapeshifter
Vexing Shusher
Voidmage Apprentice
Voidmage Husher
Voidmage Prodigy
Willbender
Withered Wretch

*Enchantment*

Decree of Silence
Holistic Wisdom
Knollspine Invocation
Rage Reflection
Spellweaver Volute
Take Possession
Thought Reflection
Wound Reflection


*Instants*

Absorb
Agonizing Demise
Arcane Denial
Assert Authority
Betrayal of Flesh
Blast from the Past
Cancel
Capsize
Chord of Calling
Clutch of the Undercity
Commandeer
Congregation at Dawn
Controvert
Counterbore
Cruel Revival
Death Denied
Deflection
Delay
Desertion
Discombobulate
Dismal Failure
Dismiss
Disrupting Shoal
Dwarven Catapult
Ertai's Meddling
Evacuation
Exclude
Fact of Fiction
Faerie Trickery
Fervent Denial
Festival of the Guildpact
Forbid
Force of Will
Fracturing Gust
Frazzle
Gaze of Adamaro
Grab the Reins
Hinder
Induce Paranoia
Inferno
Krosan Grip
Last Word
Memory Plunder
Molder
Moonlight Bargain
Mortify
Muddle the Mixture
Murmurs from Beyond
Mystical Teachings
Negate
Opportunity
Overwhelming Intellect
Pact of Negation
Parallectric Feedback
Perplex
Pulse of the Field
Pulse of the Grid
Put Away
Putrefy
Ray of Distortion
Red Elemental Blast
Remand
Rend Flesh
Repel Intruders
Return to Dust
Rewind
Rootgrapple
Scattering Stroke
Searing Wind
Seed Spark
Shattering Pulse
Shining Shoal
Shunt
Sickening Shoal
Skeletal Scrying
Smash
Snapback
Snuff Out
Soulblast
Spell Blast
Spell Burst
Spelljack
Spellshift
Spin into Myth
Spite // Malice
Starstorm
Stifle
Stonewood Invocation
Sudden Death
Sudden Spoiling
Swift Silence
Swords to Plowshares
Terminate
Time Stop
Trial // Error
Trickbind
Undermine
Whispers of the Muse
Who/What/When/ Where/Why
Wild Ricochet
Wipe Away
Word of Seizing
Wrecking Ball

*Land*

Academy Ruins
Boseiju, Who Shelters All
Maze of Ith
Prahv, Spires of Order
Urza's Factory

*Sorcery*

Acquire
Akroma's Vengeance
All Suns' Dawn
Balancing Act
Barter in Blood
Blatant Thievery
Bribery
Crush of Wurms
Decree of Annihilation
Decree of Pain
Enshrined Memories
Evangelize
Final Judgment
Flowstone Slide
Insurrection
Knowledge Exploitation
Mind Spring
Obliterate
Phthisis
Plague Wind
Promise of Power
Shattering Spree
Storm Herd
Sway of the Stars
Time Stretch
Tooth and Nail
Twisted Justice

EDIT: Had the wrong list earlier.