Leo is a amazing player and is definitely better than hiro however, I think hiro fits this team a lot better seeing that with him joining he allows Boaster to actually be able to focus on his own aim and gameplay instead of worrying about IGLing everything seeing that hiro midrounds for him, now this takes a lot of pressure of Boasters shoulders and allows him to calm down and focus.
If Leo were to come back he would have to become the midrounder role for Boaster, so its not back to a 4v5 again but this doesn't seem likely.
hiro allows Boaster to step into the spotlight, while Leo doesn't and the team is a lot more flexible seeing hiro is able to play different roles.
Overall Leo is a better mechanical player but hiro allows and enables his team to do well and this includes Boaster and shares his spotlight and willingly gives it up.
Both players are extremely good in their own right but hiro brings a better team dynamic.
This is my opinion so please don't take this to heart.
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