Expert's Corner (by ThE_HyDrA)

Academy's special buildings are based more on enchancements and artifacts that creature growth or inflicting morale penalties. The Library is a structure that can sometimes alleviate the pain of an unfavourable mage guild, and should only be invested in if your magic hero has not lucked into the preferred spells, or you would simply like to extend the range of the mage guild to cater for several magic heroes (which is not uncommon in the Academy and especially so for large maps). However, since it's a requirement for the costly Silver Pavillion, your precious resources need to be in abundance. Cost shouldn't be a problem if precious resources are fairly plentiful, though many of those would have been devoted to upgrading the mage guild and, later, Silver Pavillion if it can be afforded. Waiting until at least the 3rd level in mage guild development is recommended before buying the Library unless it is a smaller map.

The Artifact Merchant, while expensive, is a good resource for artifacts if the map is particularly scarce of these items. This is definitely not a high-priority building and is not required for any of the Academy's other buildings. The Treasure Cave, on the other hand, is an excellent building. Not only does it boost the Genie/Master Genie growth by 2 per week (a massive 66% of its base growth rate), but it also produces an additional 500 gold per day! While it requires the Pinnacle of Wishes and a rather generous Town Level 12, it should be an early investment, especially considering the relative difficulty of keeping Genies on the battlefield thanks to their low Hit Points. This helps to abate the trend, and easily gives you back your gold that you paid - almost paying for itself - and the genies - within 1 week.