I just read an article in the Champion Feedback forum that the Sivir changes are supposedly a point in the direction that RIOT wants to focus more on champions fighting each other and less on the other aspects of the game, like lane pushing, backdooring, and minion farming.
They are making it less dangerous to engage by lowering creep damage, more lucrative to actually fight champions against each other, and hasten the process at which it happens, while simultaneously removing or hindering the defensive items, like the HP pot nerf.
So what does this have to do with Sivir? Apparently, the remake was two-fold to not only give her a little more bursty feel for AD ranged, but with the change to RIcochet, lower the speed of which she can push a lane, thus giving enemy champions time to retaliate to her instead of her being able to clear a full lane in a ridiculously short amount of time. The new Ricochet acts as a bit of a limiter on how quickly she can clear, both due to slower Ricochet uses, and mana intensity.
The nerfbuff to her Ultimate is to encourage her to team fight more so that her teammates gain more use out of her presence.
Pretty much my biggest thing about this game has been playing champions and doing kind of my own thing, which is why I loved the old Sivir. I could let my team do all the PvP stuff, and I would backdoor all the time. The new Sivir's backdooring speed is much, much lower than before. She is just as comparable to Ashe clearing waves now, and her creep score at end game is far lower than I used to have previously.
The article went on to say, it probably wont be long until the game moves away from Nexus, Inhibitors, and Turrets, and becomes first to 50 kills wins.
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