The Aku Realms

:Aku Altars Appear!
:Your Aku Research is complete and the Gates of Aku have opened!
:Visit Empire of Cats to enter this dark realm...
The Aku Realms (魔界編 Makai-hen, lit. "Demon World Arc" or "Devil World Arc") are a special area unlocked after completing Unleashing the Cats, which in turn requires Wicked Cat, Wicked Tank, Wicked Axe to be cleared. To access this unique chapter, tap the spinning portal button labelled "The Aku Gates" above the Empire of Cats chapter. The Aku Realms were added in update 10.9.
==Story==
Thanks to the Empress' Research, the Cats successfully open the gates to another plane of existence. As expected, these lands are dominated by the nefarious Aku Enemies they had previously run into, but are also dotted with evil "Aku Altars" whose magics weaken the Cats to near-powerless levels. As they soon discover, these Altars were the work of a malevolent priest with frightening power and a dastardly plot nine years in the making—"Mamon", not Hargon—who works tirelessly to undo the seals placed by legendary heroes on the god of destruction—"Jagando", not Malroth—in times long past.
Although weakened to critical levels, the Cats battle it out through the Aku Realms and regain their former power little by little, one Altar at a time. Midway through, they reach Mount Aku (Mount Fuji in the Japanese Version), where Mamon attacks them and makes off with the mountain's "crystal of awakening" needed for the final step of his plan. The Cats catch up to him and defeat him once more on the Moon (Iriomote Island in the Japanese Version), only for him to escape once more and the Cats to learn that Jagando has already been revived on Mount Aku/Mount Fuji. But even the god of destruction is no match for an army of weird cats, and with Jagando defeated once more, Mamon loses everything he had worked so hard for, his spirit utterly crushed to where, for the first time in forever, he can finally get his mind off world domination and reunite with his family.(yay!) The Aku Altars' powerful seals are universally deactivated, giving the Cats full reign in other areas where they may have obstructed their progress.
As the Cats leave the Aku Realms, the Lord of Ruin's egg in their paws, Mamon parts them farewell and sends them thanks for giving him the chance to rehabilitate, but ends his message on an ominous note: "We'll surely meet again, Battle Cats. Just you wait..."
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==Explanation==
This is basically a bonus chapter of Empire of Cats, with its own map and stages, but there are some catches. First, the stages become available out of order, with Korea/Nagasaki always being the first, but after that, some stages are randomly chosen to temporarily become available for the duration of 3 hours, after which new stages are picked and those that were not completed become unavailable again. Those that were completed stay available forever (this does not include the invasion on Mount Aku/Mount Fuji). Although random, note that the selection is most likely to involve early stages and will probably not go too far after the furthest stage that is completed, meaning that after Korea/Nagasaki, you probably won't get stages in the second half of the map. Tap the "Aku Altar Appears!" button at the stage select screen to move immediately to the first of the currently available Aku Altar stages. Tapping the same button again will take you to the next available stage. 
The main gimmick of the Aku Realms is the Aku Altar and its ability to restrict unit levels. Cats are initially reverted to level 1 (only during battle) and have their + levels invalidated. After beating Korea/Nagasaki, the restriction will rise to level 2 for whichever stage to play next, then increases by one after first clearing that next stage and so on. This continues until the 49th stage is beaten and the level restriction reaches 50, with + levels staying disabled all the way. The order of the stages in the map is irrelevant for this; whichever stage you play sixth will be the one in which your cats will be forced to level 6 and so on. This means that it would be optimal to play the stages in order (by waiting for the next to be randomly picked as one of the available stages), as most of the stages are generally in order from easiest to hardest on the map, as one would expect. Not doing so may result in level 10 units having to be used in a stage balanced for level 20 ones, then maybe, level 40 units being available for one of the very first five stages, which would therefore be a free win. 
Note that the units used will still keep their current form, meaning that the level restriction only affects the starting stats (Eraser Cat, for example, will revert to level 1, but stay in True Form, so its stats will be higher than a level 1 Tank Cat).
===Stages and Rewards===
The Aku Realms' stages take place in the same locations as normal, but there is one added stop which appears as stage 30: Mount Aku/Mount Fuji, increasing the total number of stages to 49. This stage drops an Aku Catfruit when cleared for the first time. After completing the Moon/Iriomote stage, you will receive a one-time Gold Catfruit and unlock an invasion in Mount Aku/Mount Fuji, where you will encounter Lord of Ruin Jagando. Complete the invasion to receive a Platinum Ticket, unlock Jagando Jr., and strip the Aku Altar of its ability to disable + levels.
Treasures still take effect here, but there are no new ones to collect.
===Aku Enemies===
As its name suggests, the Aku Realms are home to a variety of Aku Enemies, some of which cannot be found elsewhere.
*Aku Doge
*Sinner Snache
*Cerberus Kids
*Condemned Peng
*Aku Gory
*Le'Behemoth
*Fallen Bear
*Wicked Face
*Dark Priest Mamon: Appears in stage 30, Mount Aku/Mount Fuji.
*High Priest Mamon: Appears in stage 49, Moon/Iriomote.
*Lord of Ruin Jagando: Appears in the bonus stage, Mount Aku/Mount Fuji Invasion.
The strength magnifications vary for each Aku, starting out low but reaching endgame levels in the last few stages.
===Appearance Pattern===
Compared to Zombie Outbreaks, the Aku Realms has more consistency to when and which stages will appear, which is dependent on how many have already been cleared. Every 2 hours and 59 minutes, the game will choose up to 5 random stages and then roll the die for each one; if successful, the stage will become available, and if not, the game will try again after another 2 hours and 59 minutes. The number and selection of stages that can be chosen are based on the player's current Level Seal; the higher the Seal, the greater the range of candidates for playable stages.
==List of Stages==
Below are the locations of each stage in BCEN and BCJP.
Stage	Location 	Stage	Location
1 	Korea/Nagasaki 	2 	Mongolia/Saga
3 	China/Kagoshima 	4 	Thailand/Kumamoto
5 	Cambodia/Miyazaki 	6 	Philippines/Ōita
7 	Japan/Fukuoka 	8 	Australia/Kochi
9 	Singapore/Ehime 	10 	Maldives/Tokushima
11 	India/Kagawa 	12 	Nepal/Yamaguchi
13 	Dubai/Hiroshima 	14 	Saudi Arabia/Shimane
15 	Kenya/Okayama 	16 	Madagascar/Tottori
17 	South Africa/Hyōgo 	18 	Ghana/Wakayama
19 	Sahara/Osaka 	20 	Egypt/Kyoto
21 	Turkey/Nara 	22 	Russia/Mie
23 	Greece/Shiga 	24 	Italy/Fukui
25 	Monaco/Ishikawa 	26 	Spain/Aichi
27 	France/Gifu 	28 	Germany/Toyama
29 	Denmark/Shizuoka 	30 	Mount Aku/Mount Fuji
31 	Norway/Yamanashi 	32 	United Kingdom/Nagano
33 	Greenland/Niigata 	34 	Canada/Kanagawa
35 	New York/Chiba 	36 	Bermuda/Tokyo
37 	Jamaica/Saitama 	38 	Colombia/Gunma
39 	Brazil/Tochigi 	40 	Argentina/Ibaraki
41 	Machu Picchu/Fukushima	42 	Easter Island/Miyagi
43 	Mexico/Yamagata 	44 	NASA/Iwate
45 	Las Vegas/Akita 	46 	Hollywood/Aomori
47 	Alaska/Hokkaido 	48 	Hawaii/Okinawa
49 	Moon/Iriomote 	IN 	Mount Aku/Mount Fuji Invasion
==Mission==
===Japanese Version===
Requirement	Reward
===Other Versions===
Requirement	Reward
==Notes==
*Despite also being part of Empire of Cats, the Aku Realms are much harder than Zombie Outbreaks, which is due in no small part to their far wider roster of enemies. Most of the enemies encountered are unrelated to those found in the normal Empire of Cats stages. Expect to see every trait except Relic; Stories of Legend Enemies like Brollow, Two Can and Henry; Into the Future Zombies like Zuche and Cadaver Bear; and even a few Uncanny Legends Enemies like Gobble, Zollow and Ragin' Gory.
*The Aku Altar only restricts normal levels and + levels; other upgrades such as True Forms, Talents and Talent Orbs will not be affected.
*Since the Aku Altar restricts + levels until Mount Aku's invasion is cleared, Normal Cats will have extremely low stats, for example Eraser Cat will only have 7,200 HP at Seal 20 and beyond. Crazed Cats will be much more effective since they only rely on normal levels, and have stats designed around lower levels.
*Despite technically being an extension to Empire of Cats, the Aku Realms are officially considered as their own story chapter.
==Trivia==
*The text on the background of uncleared Aku Realm stage buttons is upside-down katakana which translates to: "Stealing energy from another world; the Devils' Fortress seals levels."
*The book next to the "Aku Altar Appears!" button looks the same as Possessed Empress' cursed grimoire.
*According to the intro, the full title of the chapter is "The Aku Realms: Dark Priest's Desire".
*Although it is called "The Aku Realms", the button says "The Aku Gates", possibly meaning that the button itself is the entrance. 
*The length of Mamon's 9-year scheme is the same as between the release of Nyanko Daisensou (2012) and update 10.9 (2021), as well as how long it took for Princess Cat to finish reading every book in the royal library.
*The Aku Realms were mentioned in Aku Cyclone's descriptions, Aku Researcher's Japanese description and Evil Aku Researcher's sign before being added to the game.
*The Aku Realms' Japanese logo resembles the Japanese Ghosts 'n Goblins logo.
==Reference==
*https://battlecats-db.com/stage/s30000.html
*https://www.reddit.com/r/battlecats/comments/pg6nkg/announcement_bcjp_ver_109_is_out/
Category:Game Features
Category:Main Chapters Levels