[2020] Hey Riot ! Could we please know the probability to upgrade ?

Fair enough :).

We debated a bunch whether we should just include the upgrade rates in that article, but we were hesitant to. The upgrade chances are among the least confident tuning values we have, and, to be honest, is probably one of the most likely places we'd take value out of the system if we need to buff something elsewhere (or if, hopefully not, we've just overtuned things). While we can, and will, communicate that kind of change, it usually causes a bunch of confusion despite our intent to be clear. We wanted to see how much interest there was in the upgrade chances before signing us and players up for that.

Clearly there is an interest to see them, so I'll share them here. That said, THESE COULD DECREASE IN THE FUTURE! These may be overtuned or it may be that the reward value will better serve players elsewhere in the system.

Remember these can chain as well, but in game it's hard to tell right now.

The region reward order is not exactly the same for all regions, because some rewards are swapped around by a position or two. It's never a huge difference and the total content lines up every 4 levels.

I don't believe so. I looked at the loot tables and unless it's hooked up in a way I don't understand (which is possible), there's no upgrades on shards.