Budget Alternatives to Mercenary Knight

Balduvian Horde $0.03 2RR · Human Barbarian When this creature enters, sacrifice it unless you discard a card at random. Drekavac $0.08 1B · Beast When this creature enters, sacrifice it unless you discard a noncreature card. Ovinomancer $0.10 2U · Human Wizard When this creature enters, sacrifice it unless you return three basic lands you control to their ... Hidden Horror $0.12 1BB · Horror When this creature enters, sacrifice it unless you discard a creature card. Crypt Champion $0.12 3B · Zombie Double strike Drake Familiar $0.13 1U · Drake Flying Vulshok War Boar $0.14 2RR · Boar Beast When this creature enters, sacrifice it unless you sacrifice an artifact. Cragganwick Cremator $0.15 2RR · Giant Shaman When this creature enters, discard a card at random. Bull Elephant $0.16 3G · Elephant When this creature enters, sacrifice it unless you return two Forests you control to their owner'... Body Snatcher $0.17 2BB · Phyrexian Minion When this creature enters, exile it unless you discard a creature card. Minotaur Explorer $0.18 1R · Minotaur Scout When this creature enters, sacrifice it unless you discard a card at random. Harvest Wurm $0.19 1G · Wurm When this creature enters, sacrifice it unless you return a basic land card from your graveyard t... Fallow Wurm $0.26 2G · Wurm When this creature enters, sacrifice it unless you discard a land card. Steamcore Scholar $0.28 2U · Weird Detective Flying, vigilance Plant Elemental $0.29 1G · Plant Elemental When this creature enters, sacrifice it unless you sacrifice a Forest. Quickling $0.31 1U · Faerie Rogue Flash Avatar of Discord $0.35 B/RB/RB/R · Avatar Flying Megatherium $0.43 2G · Beast Trample Thundering Wurm $1.78 2G · Wurm When this creature enters, sacrifice it unless you discard a land card.