Ice Prison Emperor, Cocytus Greed

<Ancient World> [AUTO]:When this unit is placed on (RC), you may put the top two cards of your deck into gauge face down. [ACT](RC):[COST][Pay three gauges], choose one of your opponent's rear-guards, and retire it. [AUTO](RC):When this unit attacks, if your vanguard is grade 3 or greater, this unit gets [Power]+5000 until end of that battle.