Iād say thereās actually one even bigger reason itās so popular⦠stun absorber.
Arbustodon is front line stun protection that gives you an aggressive start to the battle against most top teams. Almost everyone wants to run some form of stun protection in their front line and Arbustodon is a very easy choice for that if youāre playing in the top level of PvP. Couple that with how an aggressive, high speed FL is very easy and effective to play so itās a popular strategy and you have Arbustodon being extremely popular.
I do fully appreciate its power but also how itās not guaranteed and it has one very specific role. All the other S+ legendaries I feel are very deserving of their slot even though a couple are not chosen by people with large accounts (Novadrake, Padrinorca, Galvbishamon) and a couple are hidden gems (Elemphox, Rosegeist). So Iāve been very hesitant to put something like Arbustodon in there due to its unreliability. Iām someone with a big account who frequently plays waifu and even in my battles I find I sometimes make it fairly useless on the battlefield. However, there are also many times itās a huge problem.
There are similar reasons for why other monsters are in the tiers they are. For example, Mortilys is insanely powerful, but requires very specific setups (i.e. you need to own certain monsters) and has an element of unreliability to it⦠so itās S tier rather than S+.
Anyway, Iām rambling but the final point I wanted to make is Iāve tried not to make the tier list just reflect the top level of PvP. However, I do think Arbustodon is great enough in that setting to go ahead and put it in S+ even though the vast majority of players should probably avoid it. I guess I should respect that players will be smart enough to understand that nuance when they look at the tier list.