Originally Posted by Akuser

What is it Eqip Upgrade? Just use same jewels for upgrade? Any tips or notes for it?

Equipment upgrade is said to be extremely expensive, costing way more than upgrading your units. So I think it'd be better to leave it for a bit later for when your team is fully leveled and evolved. If you want though, do not upgrade your LVL 1 equipment, instead try to upgrade the mid-gear equipment from the harder bosses.