Forest

Crystalline Sliver

All Slivers have shroud. (They can't be the targets of spells or abilities.)

Volcanic Island

Sidewinder Sliver

All Sliver creatures have flanking. (Whenever a creature without flanking blocks a Sliver, the blocking creature gets -1/-1 until end of turn.)

Two-Headed Sliver

All Sliver creatures have menace. (They can't be blocked except by two or more creatures.)

Cloudshredder Sliver

Sliver creatures you control have flying and haste.

Mountain

Quick Sliver

Flash
Any player may cast Sliver spells as though they had flash.

Virulent Sliver

All Sliver creatures have poisonous 1. (Whenever a Sliver deals combat damage to a player, that player gets a poison counter. A player with ten or more poison counters loses the game.)

Plains

Tropical Island

Gemhide Sliver

All Slivers have "{T}: Add one mana of any color."

Plateau

Manaweft Sliver

Sliver creatures you control have "{T}: Add one mana of any color."

Striking Sliver

Sliver creatures you control have first strike. (They deal combat damage before creatures without first strike.)