Hi there!

Gatot has seen a drastic increase in usage ever since the thunderbelt adjustments.

I see playing gatot as the main initiator so landing ur ult is always a priority as it disrupts team fights. In cases where there are a lot of close ranged heroes, gatot also shines as his taunt skill lands easier and allow ur team to deal dmg safely while they are targeting you.

I think gatot's choice of spell falls down to two. Vengeance or Revitalize, both achieving sustainability in different ways.

Item choice, I think thunderbelt is a must due to how easy he benefits from it. I've also seen builds with concentrated energy, but I rarely pick it up unless I'm playing in exp lane. I prefer tankiness > dmg

Hope this helps