With endgame the old movies come to an end and the torch is passed on to Adrian Paul as the new Highlander. This is a natural transition as Adrian is leading the Highlander TV Series and I have a feeling that Cristopher Lambert was getting a bit tired of the franchise at this time.
As with the series Endgame started to explore the lore a bit and introduced new angles on what would later be a pretty extended lore in the Highlander universe. While the movie itself is not the best, it did introduce some new dimensions and stepped away from the sci-fi and fantasy versions from previous movies into a more mysterious version.
Overall this is the second best of the Highlander movies in my opinion.