Yet another card dump (Circeus's): Virtual Booster

Mutating Plague    U  Instant Put two +1/+1 counter on target creature. Until end of turn, it deals combat damage to other creatures in the form of +1/+1 counters.	Unforeseen Consequence    R  Instant Each player loses life equal to twice the number of nonbasic lands they control. Progress has a price. Progress for progress’ sake has an especially stiff price.	Flying Counterspells    U  Creature – Spell Flying, flash When Flying Counterspells enters the battlefield, counter target spell unless its controller pays , where X is Flying Counterspells's power. 1/2	Flustered Sprite    U  Creature – Fairy Cast Flustered Sprite only if you've cast another spell this turn. Flying Dismiss (Whenever this spell becomes the target of a spell or ability, you may pay to return it to your hand.) 2/1	Inter    U  Enchantment – Aura Enchant permanent Enchanted permanent is a Plains.
Dwarven Gas Knocker    C  Creature – Dwarf Artificer Whenever a player casts a red spell, Dwarven Gas Knocker gets +1/+0 until end of turn. 1/1	Spider's Leap    C  Instanr Untap target creature. It gains reach and deathtouch until end of turn. Escalate (Then any opponent may pay this spell's escalate cost and copy it. They may choose new targets for the copy.)	Rape the Soul    C  Instant Choose one – • Remove a counter from target creature; • Target creature gets -1/-1 until end of turn.	Alien Geometry    C  Instant Counter target spell with converted mana cost X. If that spell is countered this way, you may put it on the bottom of its owner’s library instead of into that player’s graveyard.	Library Familiars    C  Creature – Rat Flying Whenever a spell is countered, put a +1/+1 counter on Library Familiars. For centuries magic was rare and revered. When sciencists figured out it was just another natural force to be manipulated, mages suddenly found themselves helpless against them. 1/1
Entropic Siphon    C  Sorcery Each opponent loses 1 life. You gain life equal to the life lost this way. Surge (You may cast this spell for its Surge cost. If you do, change its text by increasing all numbers by one.)	Ethereal Killer    C  Creature – Human Rogue Deathtouch Gossamer (Whenever this creature blocks or becomes blocked, you may return it to your hand.) 1/1	Slice Bones    C  Sorcery Destroy target nonblack creature. Bolster 1 (Choose a creature with the least toughness among creatures you control and put 1 +1/+1 counter on it).	True Berserker    C  Creature – Dwarf Barbarian Xenophobia — Whenever True Berserker becomes blocked by a nonred creature, it gets +2/+0 and gains first strike. 1/1	Swamp    B  Basic Land – Swamp

Mutating Plague (uncommon, foil)
Unforeseen Consequence (rare)
Flying Counterspells (uncommon)
Flustered Sprite (uncommon)
Inter (uncommon)
Dwarven Gas Knocker (common)
Spider's Leap (common)
Rape the Soul (common)
Alien Geometry (common)
Library Familiars (common)
Entropic Siphon (common)
Ethereal Killer (common)
Slice Bones (common)
True Berserker (common)
Swamp (basic)