Combos Utilizing Caltrops

callous giant can attack because the damage dealt to him is prevented and the other player is doomed

dueling grounds allows only 1 attacker. tap vhati to make power & toughness of that attacker 1 (til end of turn). caltrops kills the attacker

Aetherflash deals 2 damage to creatures when played while the caltrops damages when attacking.

after caltrops deals its damage, cast tremor for one red mana to do another point of damage to all attacking creatures

Play deranged hermit-4 squirrels. Attack with the hermit-Caltrops kill it-use Yavimaya hollow to regernate it for another 4 squirrels. Lather, rine, abuse, repeat.

Play Caltrops, followed by Humility. All creatures are now 1/1, and Caltrops kills them if they try to attack. Play grindstone, and use it until they run out of cards! Counterspell when needed.

if the opponets creatures attack they are killed by the caltrops. This combo really shines in a "creatureless" deck.

lashknife prevents 1 damage to your creatures, caltrops deals only 1, humility makes their creatures 1/1 therefore being 0/1 for damage purposes

after caltrops deals its damage, cast inflame for one red mana to do another 2 damage to all attacking creatures

Your opponent's creatures are screwed. By the way, don't use creatures with this.