Cocytus in particular has drawn attention for comboing with Granblue's Card of the Day, Banshee Strolling Under the Sea, a Granblue incarnation of Dindrane with which Cocytus “Я” can use to quickly grab up card advantage through a +2 and create a 9000-power booster in the process.
Grade 3/11000 Power/No Shield/Granblue - Skeleton/
Activate (V) [Limit Break 4]: [Put three cards from the top of your deck into the drop zone, choose one of your «Granblue» rearguards and Lock it] Choose a «Granblue» from your drop zone, call it to (RC), and that unit gets [Power] +3000 until end of turn.
Continuous (V): If you have a "Ice Prison Necromancer, Cocytus" in your soul, this unit gets [Power] +2000.
Continuous (V/R): Lord
School Punisher, Leo-pald “Я”
Grade 3/11000 Power/No Shield/Great Nature - Highbeast/
Activate (V) [Limit Break 4]: [Choose one of your «Great Nature» rearguards, and Lock it.] Choose two of your «Great Nature» rearguards, those units get [Power] +4000 until end of the turn, and those units get "Auto [R]: During the end phase of your turn, retire this unit," "Auto: During your end phase, when this unit is sent from (RC) to the drop zone, call this card to an (RC) without a unit."
Continuous (V): If you have a "School Hunter, Leo-pald" in your soul, this unit gets [Power] +2000.
Continuous (V/R): Lord.
Strongest Beast Deity, Ethics Buster Extreme
Grade 3/11000 Power/No Shield/Nova Grappler - Battleroid/
Auto (V) [Limit Break 4]: When this unit drive checks a grade 1 or greater "Beast Deity," choose one of your «Nova Grappler» rearguards and stand it.
Continuous (V): If you have a "Beast Deity, Ethics Buster" in your soul, this unit gets [Power] +2000.
Continuous (V/R): Lord.