Invasion

Map version updated. Changes:

- Increased the number of creatures in joinable stacks.
- Added pauses during the resurrection of heroes 3, 4, and 5. The pause is slightly longer for the Orcs.
- Improved the combat script; now, the number of summoned Cave Lords increases non-linearly with the hero's level (at level 1 - 1 Cave Lord, at level 40 - 1000 Cave Lords).
- Fixed a bug with one of the garrisons.
- The artifact "Boots of Open Passage" has been moved closer to the castle.
- Added another scroll with a portal to the city, under moderate guard.
- Removed the ability to join stacks without breaking through the guard.