Whenever a source an opponent controls deals damage to you, that player sacrifices a permanent.
6/1/2005 One permanent is sacrificed each time an opponent’s source deals damage to Michiko Konda’s controller. The amount of damage doesn’t matter.
6/1/2005 Sources that deal damage multiple times (such as creatures with double strike) will trigger Michiko Konda multiple times.
6/1/2005 Spells that deal damage repeatedly trigger Michiko Konda’s ability each time they deal damage. For example, a Glacial Ray spliced onto another Glacial Ray triggers the ability twice (once for each “2 damage” event from the Glacial Ray).