Board Thread:Bloons Wiki and BTD News/@comment-7942683-20130408035522

The Specialty Buildings in BTD5 and BTD5 Deluxe have 3 upgrades that you can purchase. However, this Wiki notes that there are 4 upgrades for all or most of the Specialty Buildings while I still can't find the 4th upgrade for any building--it seems as if they don't exist. Whats more is that the 4th upgrades for a lot of the Specialty Buildings are actually from the Premium Upgrade Shop. Could someone please clarify or help me locate the 4th upgrades for the Specialty Buildings if they exist? Thank you. 