Pair it with something that removes -1/-1 counters or adds +1/+1 counters when it comes into play and a free sacrifice outlet like Ashnod's Altar and this creature goes infinite in so many ways
Cryptic: The focus of the classic Space Hulk game that pits elite Space Marines against these purpose bred hunters, Genestealers are excellent and terrifying infiltration units, serving as the forerunners of Tyranid invasions
The fact that the final ability only saves your attacking creatures unfortunately caps its potential
There are some potential problemsweaknesses specificallyhere
Meren's second ability can return creature cards from the graveyard to either the hand or the battlefield, depending on that card's mana cost and the player's experience points
You can achieve a similar effect with a free sacrifice outlet, Mikaeus, the Unhallowed, and a persist creature like Putrid Goblin