Predatory Sliver and Sinew Sliver: One of these two slivers are usually dropped on turn two to buff your whole legion.
Galerider Sliver
: Grants your whole team flying to evade offence on the ground.
Sedge Sliver: Usually is giving your creatures +1/+1 and regenerate, which make your slivers annoying to remove.
Manaweft Sliver
: In a 5 Colour Deck, the mana base is disgusting. Manaweft Sliver is crucial to curve out your mana and start playing the needed slivers.
Necrotic Sliver: It destroys everything. I've had games where I was destroying my opponent's lands so they couldn't disrupt me. This also potentially stops some combos.
Homing Sliver: It has slivercycling. This is great for grabbing the specific sliver you need when you have another redundant sliver in your hand.
Sentinel Sliver: This makes sure you can swing in while still having blockers on your side.
Syphon Sliver
: This sliver makes great comebacks against decks that are faster than you. For example, Mono Red.
Virulent Sliver: Virulent Sliver works around life gain decks that gain life faster than you can kill.
Striking Sliver: Grants first strike to everything to make sure your attacks are as lethal as possible.
Leeching Sliver
: It grants the ability to steal your opponent's life by swinging in. This makes sure you will win the game even though they have blockers.
Darkheart Sliver: Usually your last ditch effort against decks that drain your life.
You can also include Mutavault as a sliver, because it becomes a sliver by becoming a creature.