Ramosian Rally 

Instant
If you control a Plains, you may tap an untapped creature you control rather than pay this spell's mana cost.
Creatures you control get +1/+1 until end of turn.
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Cards that do something similar expected a card that isn't here?
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Angelic Favor 100%
$0.24#24107
"If you control a Plains, you may tap an untapped creature you control rather than pay this spell's mana cost."
Sivvi's Valor 100%
$0.36#20626
"If you control a Plains, you may tap an untapped creature you control rather than pay this spell's mana cost."
Orim's Cure 100%
$0.14#29485
"If you control a Plains, you may tap an untapped creature you control rather than pay this spell's mana cost."
Lashknife 100%
$0.16#18964
"If you control a Plains, you may tap an untapped creature you control rather than pay this spell's mana cost."
Swallow Whole 86%
$0.24#19754
"As an additional cost to cast this spell, tap an untapped creature you control."