I recently watched a YouTube video about the Hussite Wagons, so this is more about the unique unit Hussite Wagon, rather than Hussites themselves
Hussites were followers of a reformer Hus (pronounced whoss/hoos or simply not like hussar). They were Bohemian people (Dawn of the Dukes alert!) who resisted Christianity at that time.
The Hussites discovered that Defensive warfare >> offensive warfare. So let us use Defensive structures in offense. Sounds like Castle drops and believe me it is like that.
The Hussite Wagon is created at a Castle as a variation of Packed Town Center, costs 400W 200G and 5 population. It has 700 HP, 2/10 armor, but cannot attack (not yet). The Elite upgrades gives +50% HP.
The movable structure, that is the Wagon itself, can move at any location. When asked to unpack, it turns into a 3×3 structure (similar to a Krepost) with 700 HP (+50% with Elite), 7/10 armor. It attacks every 2 seconds and has 6 base range. It has 3 secondary projectiles and ability to fire 5 max (by garrisioning archers).
Its attack is quite interesting. The primary projectile deals 10 melee damage, +10 vs cavalry, +8 vs camels, +5 vs infantry, +20 vs buildings. Its primary attack is unaffected by any upgrade. Its range can be altered by fletching line upgrades.
Its secondary projectiles are similar to Longbowmen. The 2ndary projectiles have 6 attack and are affected by Fletching line upgrades. As soon as Chemistry is researched, 3 arrow projectiles of 6(+3) damage each are lost and we have 2 projectiles of 12 attack, similar to Hand Cannons (these are affected by Ballistics). The 2ndary projectiles are still capped at 5.
The building receives bonus damage as buildings and cavalry only (since it is a Wagon). It doesn’t receive bonus damage as if it is a Castle.
This building can create some anti-cavalry infantry units. The building can pack again, and move to some other location when ordered.
A 700 HP building is underwhelming, but a 700 HP unit is overwhelming. Kind of both, kind of neither. The main weakness of this unit is Petards, because of the +500 damage (+700 with siege engineers).