He is used in OFFENSE, not defense, he is a counter against specific teams or swift parry in general. Do you see many people using Madame Serris in defense for example? Yet she may even be the best arena champion for offense, in any rarity. Gurptuk is also used in some dungeon speed runs with specific compositions.
i know what he is used in, i use him in 20 spider but so what. a legendary just for some tiny situational moments. its a joke really. and to top it all off i just pulled my second warchief. its like plarium is actually fucking laughing at me