[Sniffles]

I use this code for my Boss and Arena Frames:

if (unit and unit:find("arena%d")) or (unit and unit:find("boss%d")) then
-- do some stuff ~~
end

local arena = {}
	for i = 1, 5 do
		arena[i] = oUF:Spawn("arena"..i, "SnifflesArena"..i)
		if i == 1 then
			arena[i]:SetPoint("RIGHT", UIParent, -45, -30)
		else
			arena[i]:SetPoint("BOTTOM", arena[i-1], "TOP", 0, 50)
		end
			arena[i]:SetSize(230, 26)
	end

for i = 1,MAX_BOSS_FRAMES do
	local t_boss = _G["Boss"..i.."TargetFrame"]
	t_boss:UnregisterAllEvents()
	t_boss.Show = F.dummy
	t_boss:Hide()
	_G["Boss"..i.."TargetFrame".."HealthBar"]:UnregisterAllEvents()
	_G["Boss"..i.."TargetFrame".."ManaBar"]:UnregisterAllEvents()
end

local boss = {}
for i = 1, MAX_BOSS_FRAMES do
	boss[i] = oUF:Spawn("boss"..i, "SnifflesBoss"..i)
		if i == 1 then
			boss[i]:SetPoint("RIGHT", UIParent, -45, 30)
		else
			boss[i]:SetPoint('BOTTOM', boss[i-1], 'TOP', 0, 50)             
		end
	boss[i]:SetSize(230, 26)
end

All credits to Tukz