How would I get the leader with the most kills in the game?

You can use the table.sort function. By supplying a predication argument, you can tell table.sort how it should sort the array based on each value compared: a, b. By creating our predication function and filtering with the > greater-than operator, we can organize a table from highest-to-lowest elements.

Assuming you have a Leaderboard containing a Kills ValueObject, we can use it's information as our sort base.

local Players = game:GetService("Players"):GetPlayers()

local KillsTable = {} do
	for _,Player in pairs(Players) do
		local Kills = Player:FindFirstChild("Kills")
		table.insert(KillsTable, Kills.Value)
	end
	table.sort(KillsTable, function(a, b)
		return a > b
	end)
end

print(KillsTable)

Since the first element is the highest, we can find the highest by asking for numerical index one

local HighestKills = KillsTable[1]

This will give us the highest kill-number, but not the player with it, to do that, we can pair the Player with their Kills value in it's own array and store it instead of Kills alone. Since we're inserting a table with two elements, we have to recoordinate the predication function to filter for index 1 to match the Kills properly again.

local Players = game:GetService("Players"):GetPlayers()

local KillsTable = {} do
	for _,Player in pairs(Players) do
		local Kills = Player:FindFirstChild("Kills")
		table.insert(KillsTable, {Kills.Value, Player})
	end
	table.sort(KillsTable, function(a, b)
		return a[1] > b[1]
	end)
end

local HighestKillCount = KillsTable[1][1]
local PlayerWithHighestKills = KillsTable[1][2]

print(PlayerWithHighestKills.Name.." has the highest number of kills: "..HighestKillCount)

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