Muktol

The only problem that I see with Life's Legacy is that you have it only once in your deck, to few to be drawn regularly, in combination with another card that you only have twice. So it's real luck if your draw both and can use it. Also the undying from Pyreheart Wolf is a good protection against your opponents removal and thus should only be used in emergency's for carddraw or any other effects that endanger him.
I tested DotP some time ago and was not really happy about the rules nor the way it's system of getting new cards works. Personally I favor cards I hold in my hands over something digital. Sure you get to play a lot of games but when the question comes to buying a pack of cards online or for real... I'm with the real cards ;)

I don't know much about the rules and possibility's on Duell of the Planeswalkers (DotP) but here are some changes I would do if it would be my deck:
-1 Afflicted Deserter ...if you want some artifact removal use spells in your sideboard.
-2 Daybreak Ranger ...when not transformed you can only remove flying creatures, when transformed you should be able to win without this guy.
-3 Huntmaster of the Fells ...this guy needs a deck built arround him. He needs to be transformed continuously in and out of his werewolf form to be effective, which is something you don't want to happen in a normal werewolf deck.
-2 Lambholt Elder ...there are better werewolves out there
-1 Fade into Antiquity ...sideboard
-1 Life's Legacy ...I would remove this for some other carddraw spell. The problem is that you can't use this spell in response on an opponents removal and you normally don't want to loose one of your creatures just for carddraw.
-3 Primal Bellow ...with only 5 forests the chances are high that you don't have any of them on the field.
-2 Rally the Forces
-2 Windstorm ...either sideboard or remove. Flying decks are normally rather slow and the pressure you put onto them will be enough to corner them so additional removal shouldn't be needed.
-2 Elixir of Immortality ...sideboard and use against e.g. mill
-1 Beastmaster Ascension ...strong but there are better cards for werewolf decks
-1 Fires of Yavimaya ...I don't know about legality on DotP but I always find it sad when a deck looses a higher legality because of one card. You might want to take this to a local tournament someday but cant...because of a single card.
-21 cards total

Further suggestions:
+4 Village Messenger ...fast and hard hitting
+3 Geier Reach Bandit ...transforms your humans into werewolf's the moment they hit the board.
+4 Vines of Vastwood/ Ranger's Guile/ Blossoming Defense ...protection against (spot) removal
+ 2-4 Atarka's Command ...a real versatile card as it can prevent your opponent from gaining life, deal damage to your opponent, ramp or mass-strengthen your creatures
+4 Lightning Bolt ...simple and plain a good removal or damage-spell
+ 1-3 Full Moon's Rise ...+1/+0 and trample for all your werewolf's is allready a good card but you can sacrifice it any time to regenerate all your creatures. Protection against mass-removal or bad luck when attacking.
+ 2-3 Howlpack Resurgence ...costs 1 more to cast and lacks the regeneration effect from Full Moon's Rise but it's flash ability allows you to cast in on your opponents turn, basically getting a free spell when you don't have Immerwolf on the field.
+1 Pyreheart Wolf

Further suggestions:
Breakneck Rider ...faster but weaker alternative to Instigator Gang, tough it's another card that offers trample for all your creatures.
Destructive Revelry ...sideboard material. Artifact removal that also deals damage to your opponent.
Harmonize ... carddraw.
Infiltration Lens ...carddraw in equipment form
Rogue's Gloves ...carddraw in equipment form
Vexing Shusher ...sideboard material. Your spells cost {R/G} more to play but cant be countered.

Sorry mistook copy for some other effect.

Just be aware that you can't use Riku's ability on spells that you copied, e.g. with Echo Mage.
Also Spells with {X} in it's mana-cost will, when copied, be cast for X=0.

+1
I think Rune Snag could be an interesting option instead of Cancel. The more Rune Snag are in your graveyard the more expensive it get's for your opponent to counter a spell. If yo want to stick with a 'normal' counterspell then Disallow would be the weapon of your choice as it also allows to counter abilitys.
I would also take a look at some red draw/discard spells: Tormenting Voice, Cathartic Reunion or Faithless Looting.
To make way for your finishers Artful Dodge could be an option. Even if you've milled/ discarded it into your graveyard the flashback-ability will allow you to re-use it.
Baral, Chief of Compliance would also be a superior version of Goblin Electromancer.

Greetings
Muktol

Thanks for the suggestions.
Did some changes: Added 3 Bontu the Glorified and 3 Goblin Rabblemaster instead of Barrage of Expendables and Kathari Bomber. Thatcher Revolt got replaced with Hordeling Outburst and Collateral Damage with Goblin Grenade. The only thing I'm not that happy about is that the Grenade is only a sorcery.
Both Bitterblossom and Grave Pact are a little bit out of budget (I didn't give any limit's on that, I know). I'm keeping Spawning Pit for now because it's one of the few things that can sacrifice all my creatures and still gain an advantage if my opponent hits me with a mass-removal.
I also did some changes to the mana-base.

Another thing that just came into my mind would be the new Embalm mechanic:
Anointer Priest ...provides you with a solid defender and you gain 1 life whenever a token enters the battlefield on your side
Sacred Cat ...1/1 lifelink for {W} that can be re-used for {W}

I think the sacrifice outlet of my choice would be Spawning Pit. You can sacrifice as many as you need/ want and pay later to get tokens out of it. But Greater Gargadon is also a great choice, as it's a good backup plan when Pious Evangel doesn't work out and it can be really unpredictable for your opponent when you will cast it.

+1
Personally I'm no big friend of decks that destroy a higher legality for one card. You might want to take this to a local tournament one day and can't because of this one card. There are some option which you could replace Renounce with:
Bubbling Cauldron ...only 1 sacrifice per turn but stronger lifegain
Culling Dais ...no immediate effect but carddraw when needed
Phyrexian Soulgorger ...you get a strong creature that lets you sacrifice more and more creatures as longer the game goes on
Spawning Pit ...can create a 2/2 token for 2 sacrificed creatures

Spark Elemental could be replaced with the Hellspark Elemental in the sideboard. It does the same and even costs one more to play but you have the option to unearth it from your graveyard and use it again for the same cost.

Hissing Iguanar or Rage Thrower (high cmc) could be a good backup for Pious Evangel. Another, very radical, option would be to go from W/R to B/R as black offers some real interesting cards in this area.

Greetings
Muktol

Basically I added the duallands simply because I added them to each other of the beginners decks until now, but, as you pointed out, Rakdos might not be real winner with those. The only other ones that I could find where Rakdos Carnarium (which would need an explanation that you can take back tapped lands) or Lantern-Lit Graveyard. Personally I would favour Rakdos Carnarium of those. Would you also remove Evolving Wilds?
I simply limited the rarity because the rare lands all cost an arm and a leg and push the price of the decks way above any limit I would expect a beginner to pay. It's also the reason why I didn't use Lightning Bolt. You simply can show that a change of cards can make a deck more efficient while keeping it#s strategy the same, but it's cost will rise.

+1
Anointer Priest could be replaced with any of the Soul-Sisters (Soul Warden, Soul's Attendant, Essence Warden or even Suture Priest). Their body is weaker but you not only benefit from entering tokens but every creature that enters.
I would also up the number of Steelshaper's Gift to 4 but ad another artifact that you could benefit from. Sword of Body and Mind or Sword of Feast and Famine would fit to the deck tough they don't exactly help to make the deck cheaper. Sword of the Paruns or Explorer's Scope would also be solid options.
Personally I would favour Garruk Wildspeaker over Nissa, Voice of Zendikar. He costs one more mana to play and is better to ramp but he also has a built-in overrun, which can be a real matchwinner in swarm-decks.

Greetings
Muktol

I opted against Rootborn Defenses because I felt that Indestructible might be to complicated and to powerful. Path to Exile is simply way out of the budget, tough Condemn is an option.
I'm not totally convinced from Mausoleum Guard. I first played around with Attended Knight but I had enough cards for the 3-mana slot and the flyer is a better target to copy than a simple 1/1 soldier. Jade Mage would also have been an option as well as Roc Egg or Tukatongue Thallid. But in the end I decided to use 3 Guards because they would provide the deck with more flying creatures, more creatures at once and a blocker that is able to take other creatures with him.
I was looking for a good, rare, creature that would work with swarm tactics while being not overly complicated. This is also one of the reasons why I didn't choose any of the splicers, Overrun, or any other mass-affecting card. It's also the reason I haven't used any of the guildmages in the other simple decks.
If you mean Linvala, the Preserver then this would be mythic card quality and thus doesn't fit due to the deck-restrictions.

The idea behind this was that 11 damage from my opponent should be easy to get together in one turn and to surprise him with Tainted strike.
After stepping back and re-considering this idea the question is how I can get my opponent to attack when Pariah and Stuffy Doll is on the field.

Thank you for the suggestion. Basically Pariah is supposed to do that. I need Stuffy Doll and Pariah on the field for this deck to work. The outrider can only serve as further Blocker which is unnecessary when Pariah is on the field. He also can only redirect the damage onto another creature but not onto my opponent.

If you want to get a second mana when using Arbor Elf with some enchanted wood then you would have to take something like Utopia Sprawl/ Fertile Ground/ Overgrowth. When you enchant a Forest with Abundant Growth the you get a Forest that would look like this:
{T}: Add {G} To your mana pool.
{T}: Add one mana of any color to your mana pool.
You can't activate both abilitys so you either get 1 {G} mana OR one mana of any colour you wish.

I also would put Gravity Well into the sideboard because you simply don't encounter dangerous creatures with flying each and every game.

Greetings
Muktol

+1
I would sideboard Children of Korlis and add another Gatherer of Graces and Rancor for it. Next sideboard Return to the Ranks to add one more Rancor and Spirit Loop.
Conviction could be an alternative to Aspect of Mongoose.
I also would remove Sram, Senior Edificer for another Kor Spiritdancer.

Greetings
Muktol

+1
Ph’nglui mglw’nafh Cthulhu R’lyeh wgah’nagl fhtagn

A short deck- and how-to play description would be nice.
Depending on the budget I would add some search-lands to activate Bloodghast more often. I would also remove 2 Butcher Ghoul to get another Bloodghast and Isochron Scepter.
Just as information: Multiple instances of undying trigger separately, but are effectively redundant as only the first instance to resolve will have any effect.

Greetings
Muktol

A way of preventing your creatures to get shot away to easy would be the usage of enchantments with the totem armour ability. The most popular would be Hyena Umbra or Eland Umbra. Umbra Mystic will give all your auras totem armour but itself can be removed quite easily. Also it means that you have to sacrifice one of your auras, perhaps one of your bestow-creatures to protect the carrier.
I would also replace Underworld Connections with something more aggressive like Daybreak Coronet or Helm of the Gods as you have pretty high mana-costs with the bestow creatures and don't need to find a specific card to make your deck work.
Personally I'm no big fan of decks that destroy a "higher" legality by adding one card, in this case it's Serra's Sanctum. Yes, removing this card will slow you down but you might want to take this deck to a local tournament one day and can't because of one card.

Greetings
Muktol

When you want to mill with Hedron Crab I would recommend using not only 3 in the deck but 4. Also Oboro, Palace in the Clouds, or some more affordable searchlands (Terramorphic Expanse, Evolving Wilds) ,could be an idea to activate it more often.
Jace's Erasure could be replaced with Sphinx's Tutelage. Costs {1} more mana to play but has the chance of milling much more per turn. If you're going for the draw/ mill variant you should splash black or red to get access to things like Magmatic Insight or Dark Deal.
Ponder could be replaced with Serum Visions as this would make the deck modern legal. Even if you're playing it at the kitchen table you might want to use it on a local tournament later and can't...because of 1 card.
Elixir of Immortality could be sideboarded and replaced with either some control-spells like Rune-Snag, Mana Leak, Unsummon or some more creatures that help you to survive.
The only thing that really doesn't fit in here for me is Invisible Stalker. You don't benefit from attacking and it's just a bad blocker.

Greetings
Muktol

I have also posted this in your forum thread but at the moment the notification for the forum doesn't work.
The most important thing to do is to ad a good description of what and especially how you want to achive it.
The more information's you can give the community the better the help will be. This can include basic things like legality, budget, and so on. If you want further info's on that I can recommend you this article deck:
http://www.mtgvault.com/muktol/decks/why-you-should-add-description/

Also if you need general help with deckbuilding you could take a look at :
http://www.mtgvault.com/muktol/decks/how-to-build-a-deck/
This is an article deck I have translated/ enchanced that features the most basic rules of deckbuilding.