Serene Master 

Creature — Human Monk
Whenever this creature blocks, exchange its power and the power of target creature it's blocking until end of combat.
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Cards that do something similar expected a card that isn't here?
Reports become test cases the matcher is graded against before an update ships. Delvefall isn't a chatbot guessing, it compares the printed rules text of every card with plain math, and examples like yours decide which differences should count.
Harried Spearguard 83%
$0.16#14278
"When this creature dies, create a 1/1 black Rat creature token with "This token can't block.""
Crawling Chorus 83%
$0.27#6266
"When this creature dies, create a 1/1 colorless Phyrexian Mite artifact creature token with toxic 1 and "This token can't block.""
Stinging Hivemaster 83%
$0.19#15499
"When this creature dies, create a 1/1 colorless Phyrexian Mite artifact creature token with toxic 1 and "This token can't block.""
Synapse Necromage 82%
$0.16#16244
"When this creature dies, create two 1/1 black Fungus creature tokens with "This token can't block.""
Tangled Colony 82%
$0.74#5341
"When this creature dies, create X 1/1 black Rat creature tokens with "This token can't block," where X is the amount of damage dealt to it this turn."
Spitting Slug 81%
$0.31#31277
"Whenever this creature blocks or becomes blocked, you may pay {1}{G}. If you do, this creature gains first strike until end of turn. Otherwise, each creature blocking or blocked by this creature gains first strike until end of turn."
Wall of Caltrops 81%
$0.93#26175
"Whenever this creature blocks a creature, if at least one other Wall creature is blocking that creature and no non-Wall creatures are blocking that creature, this creature gains banding until end of turn."
Shape Stealer 80%
$0.33#25270
"Whenever this creature blocks or becomes blocked by a creature, change this creature's base power and toughness to that creature's power and toughness until end of turn."