My first deck description, hope this helps out :)
This is my main deck, and I've had a Lot of success with it. More straightforward then you might think. The important thing to remember is that your success is going to be determined on your reactivity to your opponent. Depending on how you play it this deck can be aggro, control, or defensive, based on your opponent. I look at each Sliver as double worth because they basically double as a creature and enchantment.
Let's start with Card Descriptions!
Creatures
Striking Sliver: This is your basic line of defense. First strike is extremely powerful in this deck because it can create an impenetrable wall when paired with Predatory Sliver and Sentinel Sliver and it's one mana cost allows you to get it in early on. I find against control decks this is a very good early option as a denier to 1/1 creatures, a target for early removal or counters, and good for early chip damage. To top it all off it builds with the rest of your slivers, and will usually end up being at least 3/3 early in the game. Another strategy is holding on to these bad boys until you drop Door of Destinies. I've won games by controlling until 4th turn to drop Door of Destinies and then following up 5th turn with multiple cheap Slivers, causing your 1/1s to suddenly be up to 4/4's or higher in one turn. Also a cheap and quick extra mana for Manaweft Sliver. All around staple card to this deck, and cannot be replaced.
Galerider Sliver: Similar importance to Striking Sliver, though somewhat more of a threat so I usually throw this out as a decoy for removal or counters so I can safely play Manaweft Sliver. Also can be a devastating finisher when you have Massive slivers in a stand-off and all of a sudden they all have flying. Another staple that cannot be replaced.
Manaweft Sliver: Arguably THE most important card in this deck. You must defend this card at all costs because it is insanely powerful. it is entirely possible to drop a Megantic Sliver 3rd turn whilst still defending yourself. for example: First turn Striking Sliver, second turn Manaweft Sliver + Galerider Sliver, Third turn you have a 6/6 Megantic Sliver with flying and first strike and all of your other slivers are now 4/4 with flying and first strike. Manaweft Sliver is absolutely essential to this deck.
Predatory Sliver: Secondary line of defense. Powerful buffer to all of your slivers, cheap addition to Door of Destinies, and all around strong card. Another staple.
Sentinel Sliver: Great card, I feel vigilance is vastly underrated, and this card works very well with Manaweft Sliver and Striking Sliver. Could be sideboarded or replaced with Diffusion Sliver if the deck has more control.
Blur Sliver: Amazing Synergy. Paired with Manaweft Sliver creates compounding mana ramp, and is in general a badass card. Great for early pressure and late game dominance. A good replacement or sideboard for this card is Belligerent Sliver if you're having trouble getting through blockers and need more oomph than Galerider Sliver
Syphon Sliver: AMAZING Card, blanket lifelink makes all of your slivers that much scarier. Having this card alive through one attack or block can completely turn the game for you. Essential Card
Thorncaster Sliver: Insanely powerful card. This card has probably the strongest synergy in this deck as works with almost all the other abilities in this deck. The "on attack" mechanic also makes this increasingly devastating, as you can wipe a board before they have a chance to even block, or can kill an opponent on attack, even if the card gets destroyed after declaring the attack the damage still goes through. Stacking this card causes it's ability to trigger multiple times which means you can select different targets from one sliver. The synergy with Syphon Sliver is also worth mentioning as it's the card that's doing damage, not another effect, so you still get the lifelink. Amazing card.
Megantic Sliver: Your finisher. Comes into play as a 6/6 and giving all your other slivers +3/+3 is invaluable. a bit expensive but mana should not be a problem for you with Manaweft Sliver. Dropping this card with a bunch of other slivers and maybe even a Blur Sliver can spell certain doom for your opponent.
Sliver Hivelord: Strangely this is the least valuable card in this deck. It's insanely powerful and can win games but is more of a finisher or reinforcement. can be replaced with Bonescythe Sliver, Sliver Legion, or even another Thorncaster Sliver if need be but the blanket indestructible is very nice. Athreos, God of Passage could also be a good replacement
Instants
Faith's Shield: Self explanatory, protection of your permanents.
Syncopate: Amazing counter, can cripple an opponent and with Manaweft Sliver you can usually trump their mana. Can be sideboarded or replaced with Transgress the Mind or Anguished Unmaking based on preference.
Artifacts
Door of Destinies: The Grand-daddy. Crazy card that makes all your slivers even stronger, good for playing against slow decks because you can drop a ton of slivers and make them big right off the bat. Don't always hold off to play this. Good for sideboard replacement
Enchantment
Detention Sphere: Self explanatory, a token remover, good for multiple iterations of cards. Good to replace with Anguished Unmaking if theres less of a threat of multiple cards.
Planeswalker
Domri Rade: Really awesome, cheap as hell and serves as removal and deck cycling. If you get to 7 the game is most probably over.
Lands
I'm not going to go over all the lands in depth because they're mostly Shock lands, but if there is one part of this deck that is not malleable it's the land. I rarely run into mana problems and I've noticed that it is a very delicate balance.
What lands you play are based on the hand you get, but theres a basic priority
1st turn nothing to play: Shock land (Stomping Ground) or a scry land (Temple of Malady) then Sliver Hive
1st turn 1 drop available: Sliver Hive first.
Don't be afraid to take the 2 Damage from the shock lands, speed and tempo is key to your victory, and Syphon Sliver will replenish your life.
Get Transguild Promenade out quickly as well, this card makes things so much less stressful, but be careful, as you're essentially out 2 mana playing this card
There you go! This deck is insanely fun and I encourage you to give it a whirl :)
