Here is a Guide for Missions available in Alvida's Hideout.

Alvida's Hideout
Missions banner
No. Mission Description Guide Reward
Thieves's Shadows!
Capture a combined total of 5 Red Robber Pensguins and Green Robber Penguins from Alvida's Hideout.
You can find Red and Green Robber Penguins in Alvida's Hideout Ch. 2, pretty easy to capture.
Red Plated Lobster
Red-Dyed Slot!
Make all your slots red during Chapter 1 "Encounter! Alvida Pirates".
You will need 6 characters in your crew, including a Friend or Helper Captain.
Take with you characters with low ATK like Treasure Turtles and shuffle orbs, attacking the enemy, until they are all red. You can also choose to take some orb manipulators with low ATK like Cabin Boys, but you have to take turns to load specials.
Red Striped Dragon
Recruit Alvida's Crew!
From Alvida's Hideout, recruit a total of 30 of Alvida's crewmembers: any combination of STR Fighters, DEX Slashers, QCK Strikers, STR Shooters, and Cannoneers.
All recruited crewmembers must be Cabin Boys.
Clear Alvida's Hideout chapters until you get a total 30 Cabin Boys. You can check which characters you need Here, it's not necessary holding characters in the Character Box to clear the mission.
Icon evilfruit
Rainbow Gem
Alvida's Booty!
In Alvida's Hideout, collect 20 Beli bags occasionally dropped by enemies.
Clear chapters until you collect 20 Beli bags, better farming during Beli x2 bonus.
Icon evilfruit
Rainbow Gem
Ultimate Damage!
Deal a cumulative total of 400.000 damage or more during Chapter 3 "Showdown!! Iron Mace Alvida" using only normal attacks.
There are no restrictions on characters or number for on Captain, Friend, and crew.
Enemies are very weak so you need low ATK but high damage boost chain like Monkey D. Luffy Gear Third.
Teams suggested:
Double Blackbeard teams also shouldn't have a problem with this.
Red Elder Turtle
Ex-Alvida Crew Rebellion!
Use recruited Alvida Pirate crewmembers to beat Chapter 3 "Showdown!! Iron Mace Alvida".
Your Friend or Helper Captain must be a Cannoneer Cabin Boy. The crew must have a STR Fighter, DEX Slasher, QCK Striker, STR Shooter, and Cannoneer.
All crewmembers must be Cabin Boys.
Make this crew:
Helper Captain or Friend
Your Crew
F0121 F0128 F0132 F0136 F0141
Blue Elder Turtle
Defeat Iron Mace Alvida Quickly!
Beat Chapter 3 "Showdown!! Iron Mace Alvida" with 15 taps or less.
Use high damage characters that can one-shot enemies without finishing the attack. This will allow you to kill only a few units per turn while stalling for specials. Bring with you 1 or more characters with a low cooldown skill that attack all enemies like Butchie and unleash them on the final round. The special will not count as one of your taps.
Another method is to use Monet Donquixote Pirates or other post turn damage dealers as Captain or Friend/Helper Captain, as the post turn damage doesn't count as a tap. You can effectively complete this task with as little as seven taps.
Green Elder Turtle
Break With The Past!
Beat Chapter 3 "Showdown!! Iron Mace Alvida" with Smooth-Smooth Fruit Iron Mace Alvida as Captain.
Use your Iron-Mace Alvida Smooth-Smooth Fruit as Captain. Helper or Friend Captain do not count.
Yellow Elder Turtle
Coby's Counterattack
Use Coby's Special "Shooting Spree" to beat Chapter 3 "Showdown!! Iron Mace Alvida".
Use Cabin Boy Coby in your crew, load the skill and kill the Boss with the Special.
Black Elder Turtle
A Woman's Battle!
Beat Chapter 3 "Showdown!! Iron Mace Alvida" using only Ms. Monday as Captain.
You can use any Friend or Helper Captain.
Create a crew with only Miss Monday, you must attack with her only.
Icon evilfruit
Rainbow Gem
100% completion reward
Miss Love Duck Miss Love Duck