Witchstalker 
Creature — Wolf
$0.29 #19155 0.00 13.3 years
Hexproof (This creature can't be the target of spells or abilities your opponents control.)
Whenever an opponent casts a blue or black spell during your turn, put a +1/+1 counter on this creature.
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Cards similar to Witchstalker expected a card that isn't here?
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Mold Adder100%
$0.12↓#14685↑0.20↑17.3 years↑
"Whenever an opponent casts a blue or black spell, you may put a +1/+1 counter on this creature."
Snake Pit88%
$0.28↓#14073↑0.12↑27.0 years↑
"Whenever an opponent casts a blue or black spell, you may create a 1/1 green Snake creature token."
Taurean Mauler88%
$0.41↑#956↑0.38↑18.7 years↑
"Whenever an opponent casts a spell, you may put a +1/+1 counter on this creature."
Managorger Hydra87%
$0.36↑#1022↑0.48↑11.3 years↓
"Whenever a player casts a spell, put a +1/+1 counter on this creature."
Ishai, Ojutai Dragonspeaker85%
$3.68↑#4727↑0.56↑9.9 years↓
"Whenever an opponent casts a spell, put a +1/+1 counter on this card."
Sunscorch Regent85%
$0.31↑#1629↑0.36↑11.6 years↓
"Whenever an opponent casts a spell, put a +1/+1 counter on this creature and you gain 1 life."
Eyes of the Wisent80%
$0.58↑#23049↓0.11↑19.0 years↑
"Whenever an opponent casts a blue spell during your turn, you may create a 4/4 green Elemental creature token."
Thundering Mightmare80%
$0.42↑#11160↑0.28↑4.9 years↓
"As long as this card is paired with another creature, each of those creatures has "Whenever an opponent casts a spell, put a +1/+1 counter on this creature.""
Titania's Chosen79%
$0.27↓#174530.0628.0 years↑
"Whenever a player casts a green spell, put a +1/+1 counter on this creature."
Predatory Hunger79%
$0.61↑#10864↑0.11↑28.3 years↑
"Whenever an opponent casts a creature spell, put a +1/+1 counter on enchanted creature."
Lumberknot79%
$0.12↓#155490.0015.1 years↑
"Hexproof"
Marchesa's Emissary78%
$0.18↓#28975↓0.0012.4 years
"Hexproof"
Forgotten Ancient77%
$0.34↑#390↑0.44↑23.4 years↑
"Whenever a player casts a spell, you may put a +1/+1 counter on this creature."
Purraj of Urborg76%
$0.97↑#28958↓0.0030.0 years↑
"Whenever a player casts a black spell, you may pay 
. If you do, put a +1/+1 counter on Purraj."
. If you do, put a +1/+1 counter on Purraj."
Kraken's Eye76%
$0.10↓#156760.0522.7 years↑
"Whenever a player casts a blue spell, you may gain 1 life."
Crystal Rod76%
$0.14↓#26801↓0.0033.2 years↑
"Whenever a player casts a blue spell, you may pay . If you do, you gain 1 life."
. If you do, you gain 1 life."
Demon's Horn75%
$0.21↓#6565↑0.12↑22.7 years↑
"Whenever a player casts a black spell, you may gain 1 life."
Sol'kanar the Swamp King75%
$0.17↓#200220.12↑32.4 years↑
"Whenever a player casts a black spell, you gain 1 life."
Freyalise's Charm75%
$0.16↓#29946↓0.35↑31.4 years↑
"Whenever an opponent casts a black spell, you may pay . If you do, you draw a card."
. If you do, you draw a card."
Citanul Druid74%
$8.33↑#28629↓0.21↑32.6 years↑
"Whenever an opponent casts an artifact spell, put a +1/+1 counter on this creature."