Harry Tunnel is the third stage in Jail Break Tunnel.
3 Korys appear as the main threat when you attack the base.
Cat Lineup: Crazed Wall Cat, Eraser Cat (level 20+19 at least), Macho Legs Cat (level 20+19 at least), Crazed Sexy Legs Cat, Paris Cat, Crazed UFO Cat, Crazed Dragon Cat, King Dragon Cat (level 20+16 at least), Valkyrie Cat and Bahamut Cat.
Begin the battle, spawn Crazed Wall Cat and Eraser Cat for defense and use Macho Legs Cat, Crazed Sexy Legs Cat and other long-range cats, trying not to hit the enemy's castle.
When the player has maxed money capacity, spawn all cat units, (stop spawning Eraser Cat and Crazed Wall Cat because they have close range attacks, as Kory's attack will create shock waves and hit the other cats behind them. It's recommended for the player to use Dark Cat instead.
After defeating all the Korys, start spamming the Wall Cats.
Cat Lineup: Only 2 Meatshields (Crazed Macho and Crazed Wall), Bahamut Cat, A Uber Rare Cat, and fill the rest with cats with a range of over 300, such as Paris Cat, Macho Legs Cat, Drama Cats, Dancing Master Cat and Kasa Jizo.
First, spam the meatshields and slowly fill up your wallet. Then spawn Bahamut Cat. You have to get all of your meatshields killed once your units hit the enemy base.
After the Korys spawn, try to get a lot of attacks or knockbacks on them. When your damage dealers are all dead, spawn Bahamut Cat again near your base to finish them off. Then beware of the magnified Black Gories and Duches and push forward.
Bahamut Stacking. Same Line up as Strategy 2. Bring a Rich Cat. Start the battle, spawn Bahamut and just produce enough walls to keep the line intact. That way, the line won't push forward or push back. By repeating this (It's recommended that you bring a Speed Up to speed up time), you will be able to stack 3 Bahamuts. That way the Korys will be defeated much more easily.
Cat line up: 3 Cheapest meatshield + Artist cat (optional?), Paris Cat, Drama Cat, Urashima Taro, Anubis, Bahamut, Unknown Cat (ANY other uber will be better).
Spawn several meatshield and paris to stay alive while upgrading worker cat to MAX. Keep enemies close to cat base. Then stack Urashima Taro, Paris Cat, Drama Cat (when enemies are kept close when start stacking, stacking is easier). Then spawn Unknown Cat, then Bahamut. When the cats almost reach enemy base, spawn Anubis. Hopefully your cats can knock back Kory and attack the base as much as possible (I managed to kill all Kory a few moments before the base was destroyed).