Chaos Arena

Chaos Arena (commonly called CA) is a timed dungeon in Bloody Ice where waves of monsters spawn in an enclosed arena. The dungeon begins once the gate inside is destroyed. Monster waves appear in sequence, culminating in a boss monster. When the boss is killed a chest appears in the center of the arena; breaking it completes the run and awards Dungeon Points. There is no failure penalty if the timer runs out.

Monsters inside Chaos Arena do not drop individual items; instead the chest from the boss rewards Dungeon Points (1–6 per run depending on level). Key drops for the Upgrade Core (Highest) and Force Core (Highest) are known to come from Chaos Arena levels 3–6. Chaos Cores used in the Chaos Upgrade System also drop from Chaos Arena.

Eternal Chaos Arena (ECA) is a harder variant requiring character level 130 or above. It is entered with a Key of Eternal and lasts 20 minutes. ECA features 15 waves and 5 boss encounters, with enemies significantly stronger than those in Chaos Arena Lv. 6. The classic ECA drops only Fragment of Chaos. In EP XLIII the Eternal Chaos Arena was renewed with a daily run limit of 10, new drops including the Essence of Chaos Guardian Ring, and other rewards.