Thagaroth, Creeping Sinkhole

Flash, Defender, Shroud
Cumulative Upkeep: {1}{b}, or sacrifice a creature.
Whenever you sacrifice or block a creature with Thagaroth, put a +1/+1 counter on Thagaroth.
Sacrifice a creature, remove one or more +1/+1 counters from Thagaroth: Put a X/X
Zombie Horror creature token on the battlefield
where X is the number of counters removed
this way.
Thagaroth can block any number of attackers.