Name:Tithe
ManaCost:W
Types:Instant
A:SP$ Pump | Cost$ W | ValidTgts$ Opponent | StackDescription$ None | SubAbility$ DBChangeZone | SpellDescription$ Search your library for a Plains card. If target opponent controls more lands than you, you may search your library for an additional Plains card. Reveal those cards, put them into your hand, then shuffle.
SVar:DBChangeZone:DB$ ChangeZone | Origin$ Library | Destination$ Hand | ChangeType$ Plains | ChangeNum$ 1 | NoShuffle$ True | SubAbility$ DBOptionalSearch
SVar:DBOptionalSearch:DB$ ChangeZone | Origin$ Library | Destination$ Hand | ChangeType$ Plains | ChangeNum$ 1 | Optional$ True | NoShuffle$ True | ConditionCheckSVar$ X | ConditionSVarCompare$ GE1 | SubAbility$ DBShuffle
SVar:DBShuffle:DB$ Shuffle | Defined$ You
SVar:Y:Count$Valid Land.YouCtrl
SVar:Z:Count$Valid Land.TargetedPlayerCtrl
SVar:X:SVar$Z/Minus.Y
SVar:Picture:http://www.wizards.com/global/images/magic/general/tithe.jpg
Oracle:Search your library for a Plains card. If target opponent controls more lands than you, you may search your library for an additional Plains card. Reveal those cards, put them into your hand, then shuffle.