Lancerlot achievement is ‘Charge an enemy with 50 Royal Knights simultaneously as the French’.
I’ve tried a dozen times to achieve this and have succeeded a few times, but couldn’t achieve this.
You can see why I judged this to be a bug by referring to the link below.
I had ~65 knights when I got it because not always all the knights charge at the same time.
this is still broken…
tried numerous times now, >50 knights were definitely charging
I’m personally not sure if it matters, but try doing it before upgrading your Royal Knights at all. Just tested with exactly 50 not upgraded Royal Knights and it pinged for me no problem.
If you’re still unable to trigger this, please report back.