No other methods for completing this map on champion difficulty have been suggested yet.
...On a two-month save, both guards can be defeated in a single attempt. After the war with the pirate Krik, approximately 80 centaurs remain :)
Справочник по НоММ-4 http://handbookhmm.ru/pamyatka-dlya-heroes-iv.html
Памятка по НоММ-3 http://handbookhmm.ru/pamyatka-dlya-homm-iii.html
и HotA http://handbookhmm.ru/vyishla-obnovlennaya-pamyatka-dlya-homm-iii-hota.html