[Xrystal]

Okay, so what I gave you will do what you want. All you need to do is utilise what I did for 1 achievement to make it work for multiple achievements.

For example:

Initialisation Stage
You could use that for loop to add to a list of achievement id, criteria id items.

Processing Stage
You could then go through the generated list of achievement/criteria ids and do what you want with them.

Here's what might work to get the first part of it working.

local addonName, addon = ...
 
-- Make sure achievements to track table exists
local achievementsToMonitor = {
    [6351] = {},
    [6975] = {},
    [6977] = {},
    -- And any others you want to grab the information for
}
 
-- Create variables for the values you are using in the loops 
local numCriteria, criteriaString, criteriaType, completed, quantity, reqQuantity, charName, flags, assetID, quantityString, criteriaID, eligible
 
 
local function InitialiseMonitorTable()
 
    -- Go through each achievement in the monitor list
    for achievementID,data in pairs(achievementsToMonitor) do
 
        numCriteria = GetAchievementNumCriteria(achievementID)
 
        -- Go through each criteria for this achievement
        for criteriaIndex = 1,numCriteria do
 
            -- Grab the data for this criteriaIndex
 
            criteriaString, criteriaType, completed, quantity, reqQuantity, charName, flags, assetID, quantityString, criteriaID, eligible
           = GetAchievementCriteriaInfo(achievementID, criteriaIndex)
 
           -- This is where you might want to decide what to do with the information while it is available.
 
            data.criteriaID = criteriaID
            data.criteriaString = criteriaString
            data.criteriaType = criteriaType
            data.completed = completed
            data.assetID = assetID
            -- Any others you might want to store in the table
 
            -- I am not 100% sure that this keeps the data in the table once you store it here
            -- But if not replace the data part with the following and see if that works 
            -- achievementsToMonitor[achievementID] 
 
        end
    end
end
 
 
local function ProcessMonitorTable()
-- Do whatever code you want to do in here and call it when you want it to be called
end
 
 
-- The usual EventWatcher code block
local eventWatcher = CreateFrame("Frame")
 
local function OnEvent(self,event,...)
    
    if event == "ADDON_LOADED" then
        local addonLoaded = ...
        local okayToContinue = okayToContinue or false
        if addonLoaded == addonName then
        
            -- If you forget to add the Achievement Addon in the required dependancies part 
            -- of the TOC do this to ensure the addon is loaded before you do any work
            local isAchievementsLoaded = C_AddOns.IsAddOnLoaded("Blizzard_AchievementUI")
            if isAchievementsLoaded then
                okayToContinue = true
            else
                okayToContinue = false
                LoadAddOn("Blizzard_AchievementUI")
            end
        elseif addonLoaded == "Blizzard_AchievementUI" then
            
            -- Make sure our addon is loaded ( hopefully by now it is )
            local isMyAddonLoaded = C_AddOns.IsAddOnLoaded(addonName)
            
            if isMyAddonLoaded then
                okayToContinue = true
            end
        
        end
        
        -- The two above checks should make sure that both addons are available before
        -- setting the okayToContinue variable to true.
        if okayToContinue then
            InitialiseMonitorTable()
        end
        
    end     
    
end
eventWatcher:SetScript( "OnEvent", OnEvent );
eventWatcher:RegisterEvent( "ADDON_LOADED" );
-- Add whatever other events you might be needing to be watched for the rest of the addons workload
-- And the appropriate section in the OnEvent function

I added the assetID into the mix as you may find this useful
At the bottom of the wiki.gg page for the criteriainfo function it shows a table highlight what the assetID will be based on the type.

https://warcraft.wiki.gg/wiki/API_Ge...ntCriteriaInfo

For example:

A criteriaType of 0 will mean that this is a monster kill and the assetID will be the monsterID. The monsterID may be it's current GUID ( the GUID gets reset periodically for some things so it may be different week to week or month to month ).

A criteriaType of 43 denotes an exploration criteria and the assetID might be an ID that represents the location. Maybe a mapID, zoneID or subZone etc They don't seem to be 100% sure of this so you might find it out through testing.

Hopefully that will help you with that first part of your addon.