First and foremost, it’s vitally important to keep in mind that Nexus Blitz is an alpha game mode. Nexus Blitz in unbalanced, ugly and full of glitches. But as an alpha game mode, we’re going to look beyond that and focus on the game’s concept and potential.
The concept of Blitz is certainly intriguing. It’s kind of like a combination of Summoner’s Rift and ARAM with challenges/events (and power-ups) added in. Things largely revolve around team fights and the challenges. Usually at least one person per team gets massively powerful and carries.
The pros of the game mode are simple. It’s fast, fun, engaging and something new. The concept is great and it could easily fit alongside Summoner’s Rift and ARAM.
The cons are a little more complex. First of all, it’d be nice to know what Riot’s intentions with this game mode are. Is it something they want to be as popular and competitive as Summoner’s Rift? Or are they just looking to add another “for fun” game mode like ARAM? Assuming it’s the latter, Blitz fits the bill well (and if it’s the former then there’s a whole peripheral set of problems).
The Nexus Blitz map doesn’t always work

From Riot
The biggest and most immediate cons are the map, the balancing and the events. Certain items and champs are pretty OP in Blitz. Because of the accelerated rate of gold, anyone who scales well quickly becomes a monster and champs who are traditionally more effective at lower levels are essentially useless. Along these lines, it’s almost impossible to stop a team from snowballing. The most fun games are the ones where both teams are evenly matched throughout, but those seem to be few and far between.
One of the reasons for the snowballing is the events and where they spawn. Although the objectives themselves are actually pretty great, they often spawn in biased locations. A King of the Hill event that spawns underneath an enemy turret is obviously much more difficult for one team to win. Likewise, a Bardle Royale that closes around a turret gives one team a major advantage.
It’s even worse when all the events during a given match favor one team. That makes it nearly impossible for one team to win unless they were already dominating from the start.
One thing that might fix this problem is a better map. While there are certainly some interesting aspects to the current map, it could be improved upon in many ways. For example, more neutral areas might help. Aesthetically speaking, it would also be cool to see the map look a lot less like Summoner’s Rift and a lot more like one of the other locations in Runeterra.
Overall, Nexus Blitz is a pretty fun game mode. It obviously needs a lot of work, but a polished version would feel right at home alongside ARAM, Twisted Treeline and Summoner’s Rift.