Combining items?

I've tried combining items to increase their grade a few times, and it's only ever worked for me maybe once so far.

Is it something where I need to select 4 or more if I want to expect an upgrade?

It depends, its all luck, im level 48 and combine all the time. Basically the more you put in the higher chance you will have of the item increasing its grade

Not so true I can stack 10 items of any grade and RARELY get any upgrade.

Yeah but its all luck. I have equipment that started as normal and are now epics.

Yeah but its all luck. I have equipment that started as normal and are now epics.

Its purely luck. 2 items to combine is enough. Sometimes I get lucky if I have 10 items to combine. In 1 of 5 tries I sometimes get an upgrade