The MTG set Ikoria introduced Hexproof counters (along with counters for Deathtouch, Lifelink, and a whole bunch of other keywords) which can be placed on permanents to give them Hexproof
Lands are like the Pokmon TCGs energy cards - except instead of attaching them to a unit, you place them on the field and tap them each turn, like a resource pool
Its a two-mana Green 1/1 with alliance, which is an ability that triggers whenever another creature enters the battlefield under your control
This is thanks to his activated ability: a simple two-mana number that lets one of your creatures slip in unblocked this turn, and gives it a +2/+2 buff if it happens to be a Snake
Its about as critical to unlocking blacks full potential as Cabal Coffers is, perhaps even a little bit more
Keep in mind that Generous Gift is your only spell that can remove problematic lands