原文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.
原文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.