Accursed Bioluminescence

Sunken (Can only be blocked by creatures with Sunken or that is also Black and/or Blue)

Whenever a +1/+1 counter would be put on a creature you control, put on double
that amount.

"Many Ocean monsters bring shadows as harbingers as it arrival. Many hope to see the shadow of a Kraken, rather than of this Creature of the
Deep" -Entry 232 of a Deep-sea hunting log