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[+1]: Search your library for a Swamp card, reveal it, put it into your hand, then shuffle.
[−3]: Target creature gets +X/+X or -X/-X until end of turn, where X is the number of Swamps you control.
[−6]: You get an emblem with "Swamps you control have '{T}: Add {B}{B}{B}{B}.'"
Each of Liliana’s abilities refers to lands (or land cards) with the subtype Swamp, not just ones named Swamp.
Liliana’s emblem doesn’t remove any other abilities of Swamps you control.
When you activate Liliana’s second ability, you choose only the target creature. You choose whether that creature gets +X/+X or -X/-X when the ability resolves. The value of X is determined by the number of Swamps you control when the ability resolves.
You can activate Liliana’s first ability even if your library contains no Swamp cards (or you don’t want to find one). You’ll still search your library and shuffle it.
