Yeah I found when I did the 40 free maga gachas I didn't get any of the showcased units, I got either units I had before or so of the non showcased ones (The ones with lower luck) which is good I guess. Though to use 40 magas and come up with Oda after getting her from login rewards is the cruelest RNG burn of all.

I have only just been able to do the 40+ Total war, you need lvl 40 senkai for the first few missions but everyone one after that you need lvl 70 or higher to clear the whole thing. Not to mention having a healer in each group to sustain them through the whole thing. That's why events like these are good, you can get a 6*, 5* and 4* of the same girl to help boost the unit numbers and increase you chances of winning. Though for the 99+ ones the 6* is the one that will be the only help.