Hero Academy was first announced in December 2018 but added only in Version 30 in June 2020. The research of a new training counts as one such use, however it is not possible to combine two researches. The Hero Academy has 10 levels, and two simultaneous actions are allowed from level 2 (similar to Alchemy Lab). It can be converted after reaching Stronghold final level 25 (so upgrading the HA, and related necessary storage, largely replaces it as the main building to develop in the base as the player progresses).
The Hero Academy (abbreviated HA) is an advanced building that can train 1-4 star heroes (in some respects faster, cheaper or better than a Training Camp) but also Trainer Heroes, 1-3* troops, and retrain 4* troops and 5* heroes.