Puschkin

Hehe, I remember when me any my friends started out and I wanted to trade away my Circle of Protection: Black to Olaf for another common. The others screamed at me "No! Don't do that!". I asked "Why not?". They said "Because if you give him that, then he has all five Circles of Protection and then he will be invincible!"
:)
Good old times.

I didn't know this is a precon. I just thought it's a deck a beginner is slapping together from what he has.

Although, sometimes cards that are crappy in our eyes may truly help them out. For example, since you mentioned Opal Mox, what is it worth if you don't have the right other cards to go with it?
Usually, when someone has a priced card for trade but only wants crap because he has a small collection, I have a quick look at his deck and throw in some other cards that I can't trade away anyway. They are then happy as Larry. It is entirely possible that both sides profit in one way or another.

Surely, and during your career, you make SO many trades, that overall things should cancel each other out.
Unless of course you don't pay attention at all and never learn anything ... those poeple exist^^

But we tend to only remember those times when we lost money and forget about those where we got lucky. For example, back in the day when Tempest came out I traded for lots of Wastelands because I had many decks that needed them, that should cancle out other trades where items lost in value.

Also, you really can't compare different times. I sold 3 of my 4 Mishra's Workshops some years ago when they were worth 100€ each. Now I could get 250€ apice. However, firstly, that was still a gain because I got them originally for about 50 DM a piece (roughly 25 €). More importantly, I needed the money back then, not now. And if I had reinvested that money in Magic, I would have gotten other cards for prices of THAT time.
See, even if you had a time machine, it would take forever to make you money. When I started (Revised era), everybody was still crazy about Shivan Dragons and Royal Assassins and Mahamoti Djinns. Even though experienced players knew that things like dual lands are better cards, prices still told a different story, Shivans went for about 15 DM while duals costed barely 10. Sure, I could trade away my 4 Shivans and get 6 duals, but then I would have to wait. A lot! I may have 6 duals now but even players that know how good they are won't give me any more than 10 DM for it since they could get them for that anywhere. And even though duals have always been some kind of hard currency in Magic no matter what new cards came out, it took them forever to rise in price. 20 years later I am glad of course that I traded for my playset of duals, however, that about 400 DM I invested there (which was a huge amount for someone young!) could have been invested in other things that could have served me equally well or even better.

Since this seems to be basing on the triplet Newt/Witch/Cauldron, shouldn't there be more copies of the Witch?

Reassembling Skeleton is better than Tenacious Dead and should replace or complement them.

Stinkweed Imp is probably better than Deathgaze Cockatrice in this.

I don't see the use of Archetype of Finality in this. Sure, it is a nice to have, but at 6 mana you can get better things these days. Minotaur Abomination is even worse. You are probably on a budget, but I bet you have more useful fatties in your collection than this one. Skeletal Vampire maybe? Would fit in perfectly.

Fallen Angel is certainly better in this deck than Sengir Vampire.

Blood Artist should be in this somewhere, most likely 4 times! Definately more useful than the Gnawing Zombie you have there (albeit not as durable).

Thunder Strike and especially Wring Flesh aren't exactly great. Terminate would serve you well instead of Wring Flesh, so does Lightning bolt and many other spells that are easy to obtain. Thunder Strike is ok - so are many, many other spells. You would probably be better off if you had something that boosts your creatures permanently instead. Since your creatures come and go, a creature enchantment won't do, but what about equipments? You probably cannot afford to run something like Sword of Fire and Ice, but what about Sword of Vengeance? It does the same as Thunder Strike plus some more and you can reuse it. Very underrated budget equipment in my mind.

Act of Treason is very good in this deck (because you can sacrifice the creature before you have to give it back), so there should probably be more than 1. These could also replace Wring Flesh.

Didn't know the Preserver. So, one of the last original rules have been bent. At least, it doesn't stop own sacrifices because that would stop sacrifices as a cost making sense.

Trickbind, like Stifle, Interdict etc. counter a triggered ability. In this case that triggered ability causes the sacrifice - it just never comes to the point where it should be sacrificed. But there is no card that prevents a sacrifice that is due (like Melira prevents you from ever getting poison counters). Same is true for Angel of Jubilation - it prevents you from using an ability in the first place (and therefore paying a sacrifice as a cost) but cannot prevent a due sacrifice effect like Diabolic Edict. Countering Diabolic Edict with a Counterspell is like Trickbinding Phantom Beast's triggered ability, you didn't directly prevent a sacrifice, you countered a spell respectively effect which just happens to be a sacrifice if it actually resolved.

"Nothing can stop a sacrifice" is one of the few rules that have not been broken yet and probably never will. Sacrifice is too quintessential to mess with, especially since it is used as a cost a lot.

But, to answer the initial question it often helps to just check the rulings for the card. I use http://magiccards.info/ for both deckbuilding and to look rules up (it has the best filter options of all databases in my opinion). Any of the phantom creatures list this as an errata:
"8/15/2010: If Phantom Beast becomes the target of a spell or ability, Phantom Beast's ability triggers and goes on the stack on top of that spell or ability. Phantom Beast's ability will resolve (causing it to be sacrificed) first. Unless the spell or ability has another target, it will then be countered when it tries to resolve for having no legal targets."

For some reason, though, that text can only be found on Phantasmal Abomination and Phantom Beast. Put generally put, a lot of rules questions can be answered by just looking up the card in question.

Fastbond is actually speed but no ramp since all it does is allowing you to put the lands you have anyway into play faster but at the cost of life and one card (the Fastbond). So, while useful in combo decks, it isn't in decks like this that need a steady supply of mana. It would actually be hurting in the long run.
Artifact mana is a possibilty or stuff like Overgrowth. However, let's wait for Jessie to decide if the deck should indeed beef up or stay as it is with a mana curve running out of steam at 4. Which makes sense if Jessie's plan is to win with a rush as plan A and if that fails with Stampede as plan B. He/she should still add Ravenous Baloths/Blastoderms in that case but adding any creature with a cc of 5 or higher would alter the deck's structure dramatically.

Actually, Echoing Truth isn't strictly better. As all bounce effects, it has a myriad of uses and not all of them require or even want that you bounce everything with the same name. For example, you can use it on your own creature in response to something that would kill it other wise. In that case you only want to save that one creature but others with the same name should stay in play.

Into the Roil is strictly better than Disperse because it does the same for the same mana but offers a kicker to turn it into a cantrip.

Then again, since this is a mono-blue deck with nothing but Islands, I don't see why we have to use 1U bouncers when you could afford UU bouncers. Good old Boomerang can bounce lands, too.

I am missing Ravenous Baloth in this deck. It isn't as powerful anymore since combat damage doesn't use the stack now but still very nifty. Also, you run Nature's Law but only have three 4-drops which strikes me as odd. Another 4-cc beast that I think is a must: Blastoderm.
I am surprised anyway that you went for a kindof weenie route even though there are so many impressive bigger beasts. Leatherbacks and Companions are very mana efficient but they don't need to be part of a tight mana curve with otherwise unimpressive sidekicks, they could as well be the distraction you need to pull the big guns. Before I checked the deck I exspected to see something around Kurgadon, Garruk's Packleader and Rampaging Baloth .

Anyway, assuming you'll go with the current structure, besides Ravenous Baloth, Blastoderms and Durkwood Baloth (see discussion above about one-drops):
One of the beast beasts ever is Gurzigost! Indrik Stomphowler gives you the ability to kill enchantments and artifacts, however, he also costs 5 mana. I also like Molder Slug in that slot but that's more for multiplayer. Yet another fantastic 5-drop is Thragtusk, also very great and versatile. Skyshroud Warbeast is a cheap drop that I would usually recommend in a beast deck, but knowing that you'll face other tribals that are mostly mono-colored or two colours max the Warbeast will suck.
Tower Above is an underrated pump spell. The wonderful thing is the provoke part. Paired with the pump and wither this is a kind of creature removal because you can force one annoying creature to block. Might even be better thanthe Stampede you have there. Of course, that's assuming again that you play against random decks - as long as the other decks of the challange are as straight forward as this one, Stampede is probably better.
The mana base could need some work. Consider: Yavimaya Hollow, Mystifying Maze (you are weak against flyers), Mishra's Factory, Miren the Moaning Well.

BTW, the Arcbound creatures (including the Ravager) are beasts, you could build a nasty deck around those and still call it a beast deck. Of course that would change the deck completely and maybe not what you were looking for in the spirit of this challenge. But if you do, don't forget Fangren Marauder.

The Seal is what I would go with. You have enough vanilla creatures and yet another one won't contribute much. But that Seal gives you some combat tricks and works wonders on your tramplers. Any Giant Growth effect can turn into card advantage by saving a creature that would have died and killing an opposing blocker/attacker that would have survived.
Otoh, the Charm is of course very flexible in this deck as well, I just don't know if I would play it first turn if I had it in my opening hand since the other two options will most likely be more useful later on in the game.

EDIT:
Perfect one-drop: Durkwood Baloth!

What scares you about Glacial Chasm? The life payment is actually an upkeep cost and that means optional. You can always decide to not pay it and let the Glacial Chasm die. You can drop it the turn you cast Hurricane and sacrifice it next upkeep, never paying a single life, just a land, and attack again if needed.

I'll have a look at the others when I find the time. Should they be away of each other? Or should I tweak them individually and try to not metagame?

Stream of Life is horrible! At the very least, replace that with Taste of Paradise ... but in this deck it should probably be Oracle of Nectars instead.

Then again, I am not sure if you need lifegain at all. You want to kill with big X-Spells and don't want to die yourself ... enter Glacial Chasm. Solves other problems, too, like opposing hordes of attackers that you can't afford to block because then you would lose valuable mana.

Fog. There are some dozens of spin-offs of this card, you have lots of mana in this deck and you chose the plain old vanilla one? Respite grants life, Constant Mists and Moment's Peace can be used more than once and my favourite is Spore Cloud, both for the old-school-ness factor and because it buys you two turns.

You could also consider Bubble Matrix since you plan to win via X-spells and not by attacking. This would protect your creatures from destruction as well as turn them into formidable blockers. But, you probably won't need the latter if you pick the right Fogs and include Glacial Chasms. Protecting your creatures, otoh, is key, because this deck will do nothing if creatures are swiped. Of course, adding stuff like Bubble Matrix somewhat dillutes the deck, but personally, I don't like all-or-nothing decks, first, because I feel uncomfortable with them, secondly, because they rarely result into fun games - they usually end quick one way or the other.

Won't comment on the creature mix, though, too much math involved to find the right mix of mana rampers :P

I'd consider Snakeform if my big guys had trample but alas, they don't. Since I can't deal with flyers except for that single Nessian Asp, I am thinking about Hurricane as a (mass) creature removal measurement. Druids should be able to influence the weather and maybe summon a little storm, right?
Also, Druidic Satchel and Snake Umbra should be in this somewhere, but what to take out? As always, I place all candiadtes in the sideboard.

Yeah, besides livegain and prevention there are other things missing: Most notably creature removal (and I think this should be priotized over fog/prevention because there are so many creatures with nasty non-combat effects), but also graveyard-hate.
Adding this will most likely be out of theme (and I threw this deck together in less than an hour). It will take some time to find solutions in-theme, just wanted to give you the raw version early :)

I am considering bounce of some sort. It could be used as defence but also be used to reuse the Mystic Snakes and Oracles. Then again, then I enter the realm of "not that again", so maybe I won't :P

Stay tuned.

I know, no offense taken.
Also, many times even a suggestion that I don't incorporate will spawn other ideas in one way or another. Just by explaining why I won't use card X helps re-evaluating the deck.

Here it is, Druids & Snakes:
http://www.mtgvault.com/puschkin/decks/druid-basket/

I own two Abyss but no Magus of the Abyss :) I don't put decks online for others to copy, I just use MTGVault as a tool to build and archive my decks and to get some help if necessary, so budget is no concern for me. But I agree that a third Abyss-effect might be needed. But I might as well add Demonic and/or Enlightened Tutor to just fetch what I have.

My decks are for multiplayer, speed isn't that big of an issue, and while Scythe Tiger may be cheap, he costs me a land, slowing me actually down. Humble Budoka, as an otherwise vanilla creature, doesn't make the cut - what's a 2/2 gonna do these days? Takklemaggot, Death Match and Abyss cost 4 mana each, so creatures can cost 3. I'd rather add some cc2 mana ramp than a vanilla shroud creature.