Panik8

I'd simply add stuff to ramp that mana up better/faster and/or stuff to make sure Piper/Rector/Amulet are reliably used. Heck, just draw Sample Hands, you'll see what I mean, so far, I drew a dozen of them and only saw one hand I'd consider "decent", which is, that actually would've got an Eldrazi in play on turn 5.

Like I said,...

"This leaves you very vulnerable against Aggro decks and I already established how any deck with removal will crush you. Control decks would be even worse, since by the time you get the Eldrazis in play, they'll likely be able to control them, or, at the very least, lock them down. You can probably beat some combo decks, if they take too much time to get going."

I stand by that statement. I don't see how the fact this is a casual deck changes the relevance of that statement, pal.

Unless, maybe, you know people who build decks that are neither aggro, control, combo nor removal?

Sorry, I'm only trying to be realist here. This kind of deck looks great on paper, but in reality, it's often boring to play, easy to stop and generally inefficient.

Does this even work?!

No offense, but as far as I can tell, you have nothing to ramp your mana up, so you rely on 3 (12) cards to get your big creatures in play.

Elvish Piper is nice, but without Haste, Shroud or Hexproof, it's very easy to get rid of.
Academy Rector is also nice, but without a way to sacrifice him, you might never get to activate its ability. Although once he's in play, opponents can't really afford to attack you with anything this can block.
Quicksilver Amulet might be your most reliable way to get your Eldrazis into play, but again, everyone should have Artifact removal, if only in their sideboards.

I like the idea, but I don't see it working against a decent deck. It's impossible for you to get anything in play before your 4th turn, and then until your 5th turn if we're talking about your "good" creatures.

This leaves you very vulnerable against Aggro decks and I already established how any deck with removal will crush you. Control decks would be even worse, since by the time you get the Eldrazis in play, they'll likely be able to control them, or, at the very least, lock them down. You can probably beat some combo decks, if they take too much time to get going.

That's why people usually go with Tinker for this kind of deck.

That said, if you do manage to get your deck going, you'll be near unstoppable, but I simply doubt you can get it going fast enough to win reliably against most decent decks.

Considering you're already RG, I'd go Food Chain. It works really great in Goblin decks, even more so with Goblin Warchief in the deck.

Basically, with a Warchief and Food Chain in play, a 1{R} CCM Goblin can be put into play for {R} and sacrificed (to Food Chain) for {R}{R}{R}, which can be used to play a 4CCM Goblin, like the Ringleader.

You might also want to add a couple Sharpshooters and a couple Prospectors, so you can sacrifice any 3 Goblins at any time to deal 5 or 6 damage...

Basically, you'd tap Sharpshooter for 1 damage, sacrifice a creature to Prospector for {R}, thereby untapping the Sharpshooter, tap it again for another 1 damage, sacrifice another creature to Prospector, untapping the Sharpshooter again, tap again, for another 1 damage, then sacrifice a 3rd Goblin, to the Commander, this time, to deal an additional 2 damage, and also untap the Sharpshooter, yet again, tap it again for your 6th point of damage total, or leave untapped for later use.

Also, using both Food Chain and Prospector allows you to cut down on lands, assuming you're not shy about using mulligans.

Considering the rest of your deck, an ideal start would go something like...
T1: Mountain -> Lackey
T2: Mountain -> Swing with Lackey (ideally unblocked, put Commander into play for free) -> Instigator
T3: Taiga/Wooded Foothills -> Food Chain -> Swing with Lackey and Instigator (ideally unblocked, put Ringleader in play or Matron to fetch a Ringleader) -> Start Sacrificing creatures to the Food Chain, sacrifice anything you can, except Warchiefs, Sharpshooters, Piledrivers, a Commander and a Prospector.

Actually, you'll probably want to add 2x Ringleader and maybe 2x Matron, so the feeding chain never breaks. I play such a deck and can reliably put most of my library in play on turn 3, then attack with everything (incl. a few pumped-up Piledriver), then sacrifice whatever's left to finish it up, if necessary (which it likely won't be, unless you're playing a 4+ player FFA multi-player format).

I made my Vintage Food Chain Goblin deck available, if you want to see what I'm talking about. I guarantee you no one will want to play against you. The only thing that can stop my deck is a Wrath of God (or similar mass removal), only opponents rarely have the opportunity to play them on the 3rd turn, especially if you played first and they only have had time to put 2 lands in play.

My deck -> http://www.mtgvault.com/panik8/decks/panikgoblin-vintage-2/

This might be obvious, considering you're playing Blue, but I'd add something to draw cards and counter spells, maybe also something to control enemy creatures. I'm not sure what format you're going for, I'm assuming Legacy/Vintage considering Ghostly Wings is too old for Modern.

Here's some suggestions, in no particular order. I tried to avoid very expensive/rare cards.
Draw: Last Thoughts, Skyscribing, Sphinx of Magosi, Think Twice
Counter: Bone to Ash, Daze, Counterspell, Condescend, Cryptic Command
Control: Roil Elemental, Control Magic, Beguiler of Wills, Simic Manipulator

I like to use both Llanowars and Arbors, allows to play less lands and have more Elf creatures in play faster and more reliably.

Edit: I also use Gaea's Herald, Jagged-Scar Archers, Nullmage Shepherd and Tajuru Preserver in the sideboard, for whenever I might need them. Rhys the Exiled would also fit with the deck's theme.

Nice deck.

Llanowar Elves, a couple Joraga Warcallers and maybe Elvish Harbingers so you can "fetch" the right Elf at the right time would make this deck even better, in my opinion. Then, you'd have to sac 10 cards, I'd go with the Visionaries, Tracers, a Forest and an Oracle.

That said, I'm sure this deck is doing fine as it is.

Long story short, the hardest part is to limit yourself to as few Elves as possible, while being as hard to counter as possible.

You want Wirewood Symbiote. It's not an Elf, but it allows you to either untap your Elves or to return them to your hand (one at a time, anyway), should someone try to get rid of them.

Priest of Titania is also a great Elf that's somewhat better (faster) than the Elvish Archdruid.

Then, there's Seeker of Skybreak or Wirewood Lodge to untap all those Elves.

I'd also consider something to draw cards, like Sylvan Messenger, or my favorite in this kind of deck, Collective Unconscious (I've played my entire library on turn ~5 with that and a few other cards, I stopped playing it because it was so ridiculous, but then, Primal Surge is even better) or even Wirewood Herald.

You'll want something to give Haste and/or Hexproof/Shroud to your creatures, like Concordant Crossroads, Swiftfoot Boots or Lightning Greaves.

Ambush Commander is another great card, especially if you're playing Elvish Promenade and/or "X/X", "+X/+X" or any other "X" elves. It also works great with Wirewood Herald or any other Elf that has an ability activated upon death.

Oh, and make sure you run 4x Llanowar Elves, 4x Fyndhorn Elves and/or 4x Arbor Elf. See how many you want to use, but those will help ramp your mana up fast and get you a lot of Elves in play, fast, which is what Elves deck are all about. You can easily drop 4 Forests and play 4 Fyndhorn Elves or Arbor Elf instead.

Take a look at my Elf decks for ideas...
Here's my Mono-Green Vintage Elf deck: http://www.mtgvault.com/panik8/decks/panikelf-vintage/
And here's my Green/Black Modern Elf deck: http://www.mtgvault.com/panik8/decks/panikelf-v102modern/
...I ended up splitting my main deck into two, and they're still both very powerful in their own ways.

Possibilities are endless, but make sure you have something to draw cards, otherwise, you'll be easy to stop if/once you run out of steam. In other words, if an opponent has as many removal as you have creatures, you're screwed, and since that's pretty much the only way to stop an Elf deck, you want to make sure you can draw cards to keep the aggro up through the removal. Haste is also great so you can play a ton of Elves via your near-infinite mana, then tap them all to pump them up and finally attack with the deadliest ones.

Sorry for the wall of text, I'm very passionate about elf decks, let me know if you want more ideas. I posted a lot of stuff on this deck, too, if you want to check it out...: http://www.mtgvault.com/benware/decks/elf-invasioncomments/

Cheers.

You have so many 2CCM instants, I'd try to fit a couple Isochron Scepters in this deck.

Why Fling? Isn't your biggest creature Krenko, at 3/3?

I agree, I checked it out, too.

Have you considered Ooze Flux?

I updated my deck.

Great deck! Here's some suggestions, feel free to disregard them if you disagree, it's not like what follows is "tried, tested & true". :)

Considering Parallel Lives stacks exponentially, I'd play 4 of them. And if we do that, we might as well play 4 Awakening Zone and Spawning Breath. I'd also recommend at least 2 Mycoloth. To fit those 8 new cards, I'd remove 4 Abundant Growth and 4 Harrow (and 2 Predator Dragon, if you want to play Mycoloth instead, looks like a better option to me, Preyseizer Dragon is also very good or Thromok the Insatiable). Mogg War Marshal is also somewhat better than Krenko's Command/Dragon Fodder, but I'd actually replace the Llanowar Elves with it.

I think this way you'd generate a lot more tokens on a more consistent basis, at the cost of mana-versatility, which shouldn't be much of an issue in this deck. If it is, you could simply replace some Forest and Mountain with more dual lands.

Finally, I'd sideboard some removal and other useful stuff, something like... Skullcrack, Firespout, Savage Twister, or whatever you think you might need to counter your friends' decks.

In fact, I'll create a deck with all those suggestions, to show you exactly what I have in mind...
http://www.mtgvault.com/panik8/decks/panikdevour-modern/
...let me know what you think.

As was suggested, focus on Elf creatures for mana, add Elvish Archdruid and Priest of Titania, but also Umbral Mantle, which, once equipped on Priest of Titania or Elvish Archdruid with 4 or more elves in play, will generate infinite mana. Basically, your ideal game would look like this...
T1 -> Forest (1 total mana) -> Llanowar/Arbor
T2 -> Forest (3 total mana) -> Priest of Titania + Helix Pinnacle (0 counters)
T3 -> Forest (4 total mana, excluding Priest of Titania) -> Llanowar/Arbor x3 (so Priest of Titania can be tapped for 5 more mana) -> Umbral Mantle + Equip on Priest of Titania, infinite mana, win the game on your next upkeep.
...obviously, you won't get a perfect hand every game, but if you draw those 10 cards (Llanowar/Arbor x4, Forest x3, Priest of Titania, Helix Pinnacle and Umbral Mantle), and no one does anything to counter you in any way, you win.

I'd replace Fireball/Disintegrate with Banefire/Kaervek's Torch, other than that, this deck looks very hard to counter, without the right cards. Good job!

Hover your mouse cursor over "Creatures" and a "Add" button will appear right to the left of "Creatures", click it once and the "Search / Bulk Importer" form will appear below your deck. Alternatively, you can move cards from your Sideboard to your Deck (or vice versa) by hovering your mouse cursor over the name of a card, whch will make a small arrow and a small trashcan appear next to the card's name, the arrow will move it, the trashcan will remove it.

Edit: Also, when you manually edit the number copies of a card you're using, and pretty much anytime you add or remove cards, try to "hard refresh" your deck by going to the "Draw Sample Hand" or "Deck Stats" page and back, somewhy, the site seems buggy when you try to do too many changes at once, although that may be based on browser compatibility, or something else, I'm pretty new to the site too.

I'd remove 2x Jarad, Golgari Lich Lord and 2x Primordial Hydra (or whatever card you think you can do without) and replace those with 4x Treasured Find, which would synergize very well with Grisly Salvage and Jarad's Order. As it is, you send a lot of cards to the GY, without any way of getting them back into your hand, unless I missed something.

I assume it's to feed Tinker.

Yeah, I guess it's just a different way to achieve a similar result, but still, the few black cards you use here make all the difference. For instance, I wouldn't need to use 4 copies of some cards (like Gorgers) or 2 copies of my Legendary Creatures, if I had Wort or Birth Rite to fetch them back from the GY if/when they die.

I should play my deck tonight, I'll post about how it went on my deck's page.

Now I have to find a way to splash into Black, those cards really make the deck a lot better.