A creature with skulk can’t be blocked by creatures with greater power. (See rule 509, “Declare Blockers Step.”)
May 3, 2019 · War of the Spark
You choose which creature to sacrifice as you choose to pay a spell’s emerge cost (see rule 601.2b), and you sacrifice that creature as you pay the total cost (see rule 601.2h).
January 25, 2019 · Ravnica Allegiance
You choose which creature to sacrifice as you choose to pay a spell's emerge cost (see rule 601.2b), and you sacrifice that creature as you pay the total cost (see rule 601.2h).
July 22, 2016 · Eldritch Moon
You choose which creature to sacrifice as you choose to pay a spell’s emerge cost (see rule 601.2b), and you sacrifice that creature as you pay the total cost (see rule 601.2h).