This event feels way too grindy, even with the bonus scarlet credits you can get for doing well. For one thing, even if you put in the effort and invest three hours, there's no guarantee that your hard work will be rewarded since it's very possible that not enough other people will be taking out murexes to reach the goal of 100. In the instance I just ran, there were a ton of people doing ground missions, and for awhile I was getting a ton of kill codes while doing murex runs; but then at some point I just stopped receiving codes, even though the relay chat said that people on the ground were still sending them. It stinks that I was putting in as much effort as I could, even getting first place in kill codes received, but we still got less that 50/100 murexes in our instance over three hours.
I think that the event needs to be made less grindy; I can't imagine how anyone except people like me who have all the time in the world could get all the event exclusive rewards, let alone touch the arcanes. It's almost as bad as the dog days of summer event awhile back. Also, I think it would be a big boost if entering murex raids prioritized putting you in a squad over putting you in your own railjack; that would be a big help to running those raids quickly, and some people simply aren't equipped to run the raids solo, even if they have their own railjack.
I appreciate all the work that DE has put into this event and the concentrated effort they always make toward pushing out hotfixes to stomp bugs and crashes. I think this event could be a ton of fun and feel very rewarding if you were able to earn rewards at a rate more proportional to the amount of time and effort that is being asked of you. Also, please offer an explanation of how the bonus scarlet credit rewards after defeating 100 murexes work; I had to find out about it through Tactical Potato on YouTube.
Edit: Within 15 minutes of posting this, hotfix 3 dropped and allowed murex raiders to choose to fill squads or host, which is awesome. Y'all work fast! Thank you! Also, for the record, even though we didn't kill 100 murexes, I still got a message from Little Duck with an emblem and 10,000 scarlet credits after the timer for the instance finished and I restarted the game. I probably shouldn't have received that, but I'm certainly grateful and will take it. I still think that killing 100 murexes for this reward is a steep price; maybe you should get that reward regardless of killing 100 murexes, and then get a bigger reward on top of it if you do kill 100?