Party members must break the empty crystal, or else the trapped player's HP will slowly drain until they die. After a short time, an empty crystal of the same color will spawn somewhere in the room. Additionally, anyone in close range will be inflicted with Frozen (Status), which can be negated with a Toy of Sparkling World. When filled, the gauge will activate Crystal Prison, which traps the player inside. Each time a skill that requires Clear Cube Fragments is used, the gauge fills up faster. During Glacial Planet, the "A cold wind is blowing" gauge appears above each player's head and slowly fills up by itself. Glacial Planet: Rosen can be damaged at almost any time during this phase, but cannot become groggy.
After 20 seconds, every ablazed hex will explode and all party members should gather in the center as Rosen becomes groggy for 10 seconds. Have all four party members spread out in the corners during this phase, use Leap and keep jumping until the duration wears off and carry plenty of Healing Kits until the phase is over. At a certain period of time, Rosen can create Hex Explosions from those ablazed panels. Standing on the ablazed hexes will cause heavy damage similar to a Burn (Status) effect. Flame Planet: During this phase, Flame Floor is enabled and every hex panel that party members step on becomes ablazed.Planets Phase: Rosen summons four different planets that rotate around him as they are shared among both parties Universe-wise and he'll consume one of those planets that activates a phase with different patterns in a non-randomized order.he'll transform the ground similar to Executioner Belial's Tile Transformation that lets him use Hex Pillar depending on his hand movement and regardless of what planet phase he's in. Hex Panel Transformation: When all parties in their respective universe enter Rosen's room.Using the force of these planets, Rosen split himself into two halves being Black & White Universe. If he finds a strong opponent, Rosen will personallyįight them in his own universe with planets rotating around himself. Rosen is the final boss of Fiend War and the strongest one in Cosmofiend.