Grow the Hive

As an additional cost to cast Grow the Hive, you
must control a Flood Army creature token with
a power and toughness of 4 or greater.
Every time a non-flood creature dies, amass
Flood 1. (Put one +1/+1 counter on an Army you
control. It's also a Flood. If you don't control an
Army, create a 0/0 black Flood Army creature
token first.)