If we talk about all stands’ functions, I believe the two greatest is Tusk act.4( Johnny) and GER, Tusk act4 has the ability to track its enemy in all multi universe, and GER can absolutely make all of its enemy’s attack useless. Comparing them both, I believe GER is the greatest stand ever, but I don’t think Giorno can be aware of that, because even himself don’t know everything about GER
