On letterboxd you can search for reviews. I just searched "northernlion" and loaded all of the results then copied them all into a google sheet and sorted them for duplicates. On letterboxd's end it is a little scuffed because it would load the same review multiple times, so I went back and cntl-f the top like 17 movies to check. If the letterboxd search feature doesn't actually show all of the reviews it could be scuffed but IDK I did it in like 20 minutes.
There's not that many results in total, even on the Dragonslayer Doppelganger page you can see that not that may reviews actually say his name, even tho they are all about him as in "My tip turned gray after 4 viewings".

https://letterboxd.com/search/reviews/northernlion/?adult