Cotton and Eclair's Stall-Out Gang

Guide

I've been using this simple cheesy stall comp for Arena Defence for ages.
My first interaction with this setup was a nightmare, and I instantly knew I had to try it myself. I've never gone back since! (Currently, my defense power with this setup is 298,234, and it's won against teams with over 600k power).

When at 3* or higher, Eclair does formidable damage without Searing Raspberry toppings, so having him on Swift Chocolate is more viable here since you'll be prioritizing his weakness debuff over his damage. When Eclair applies weakness and Cotton moves afterward, her sheep will knock back into the middle row where most people keep their DPS cookies (Sea Fairy, Frost Queen, Sorbet Shark, Etc). Since Eclair's skill prioritizes high ATK enemies, this means that with the right setup Cotton can stun them and gains a massive damage boost for her sheep herd before Eclair's follow-up attack. This stun allows the rest of the team time to apply buffs and prepare for the next rotation. Additionally, while the Shield buff isn't too reliable consistently, it can help pull a match out in a pinch over time with slow-burn defeats on the enemy team.
Cotton and Eclair should run full Cooldown sets. For Cotton's Substats, prioritize Cooldown/ATK/DMG Resist. For Eclair, prioritize Cooldown/ATK/CRIT%. If you can't do CRIT%, ATK Speed or DMG Resist are fine subs- just keep in mind he's your only true DPS cookie on this set. If you can't run full Cooldown on both, prioritize Cotton on Cooldown and Eclair on 3-piece ATK and 2-piece Cooldown.

Hollyberry is the primary tank for this team; though being one of (if not) the best Defence Cookies in the game, that's to be expected. Since the other cookies have reliable HP and Defense already, Hollyberry is much less likely to be downed in the first wave of attacks after using her skill since the rest of the team isn't taking as much damage themselves. Strawberry crepe takes up the rear for her here with their damage reduction buff; this should ideally be applied to eclair and cotton, but if it applies to Parfait you have extended time to gain buffs and healing.
Hollyberry and Crepe should run full DMG Resist sets. Ideally, you want your substats to be DMG Resist/HP and either DEF or Debuff Resist. Cooldown is also a good substitute for HP, but they'll benefit more from additional health or DEF than Cooldown reduction (increased cooldown can mess with the speed tuning of Eclair and Cotton if you aren't careful). If you can't run full DMG Resist on both, have either Hollyberry on Full DMG Resist and Crepe on 3-piece DEF and 2-piece DMG Resist or 2-piece Amplify Buff.

Parfait is the wildcard in this setup. She's already known to have one of the best synergies with Cotton Cookie, and with the Jelly Watch, Parfait gives the team a well-needed booster in the first round. With two periodic healers, the team's healing becomes much more viable and less of a struggle to manage long-term.
Parfait can be run with various toppings based on how you want her to handle her role. If you want to prioritize her debuffs for early fights, run her on 3-piece Amplify Buff and 2-piece Cooldown. This setup is also good for Early-Mid game Story mode. You can substitute her 2-piece cooldown for 2-piece DMG resist to increase her survivability. You can also run her either 3-piece DMG Resist and 2-piece Cooldown or vice versa if you want to prolong her stall potential, but keep in mind that her buffs will be far less sustained making her less viable when running against the likes of Frost Queen or Dark Choco.

Insignia of the Indomitable Knights is this team's trump card; this is what is often the last thing keeping you winning. With every downed cookie, the insignia restores a small amount of HP to all your existing cookies, which is a godsend for stall teams like this one. Additionally, the last effect that makes the last standing cookie immune is incredible- if the enemy is thinned out to 1 or 2 cookies, Cotton's immunity allows her to heal significantly while out-stunning out the enemy. Squishy Jelly Watch is the other key item, but it's a fantastic treasure regardless of where you use it. For the middle slot, I keep Blind Healer's Staff to better assist in healing Eclair, Holly, and Parfait.

I'd recommend against using the Seamstress's Pin Cushion, since Cotton's sheep herd only stuns the first time they're summoned. The cushion extends the time that the sheep are on the field, thus minimizing the maximum stun potential you need with this team. If you want to instead maximize better damage you can use the scroll or the jelly bear candy to allow Eclair to do more independent damage. You can also use the Durinaeer's inner tube for better survivability for Crepe and Holly, but you want to make sure they get the buff- not the others.

Substitutes: If you don't have Hollyberry Cookie or Strawberry Crepe, Cocoa Cookie is a solid substitute for either- her Stun Immunity buff is greatly helpful and she's a third periodic healer for your setup, further diminishing the need for Blind Healer's Staff. Tea Knight cookie also picks up the slack if you don't have Strawberry Crepe or don't have them built- Tea Knight can provide additional buffs and is best when paired with Indomitable Knights anyways. Other substitutes for front liners here are Madeline (who can deal good damage and gains his own interruption immunity) or Moon Rabbit (for heals and shields on defeat). If you want to increase the stun-lock capability of the team and give a higher damage boost Sea Fairy is a viable option, but make sure she doesn't follow up with Cotton right before or after without a break since their stuns can overlap. Eclair and Cotton unfortunately are relied on for this team comp, so without them, you won't be able to fully utilize this staller. You can, however, shift the team to a more offensive composition if you don't have Eclair with Pumpkin Pie, though you'd be better off using a Summon team over a stall team in that case.

Anyways, that's it! My builds aren't great but they work for me. Hopefully, they work for you, too.

With lots of care,
- Spookee of Kingdom Mothball