Star Fort in 2.4.0

[Arbogast]

2.4.0 introduces the 'Star Fort' more expensive than the 'city walls'.
But the help button are identical.
So, what's the difference?

[Alien Valkyrie]

You're using the Default3+ ruleset, right?

[Arbogast]

Right, but what's the answer?

[Alien Valkyrie]

The star fort was added by the Default3+ ruleset, and you could find the answer there. But I'll tell you anyways: In Default3+, the city walls don't protect your cities against post-gunpowder units that good, and don't protect them at all against modern units. The Star Fort is basically Level 2 city walls, it protects your city against Gunpowder-era units pretty good, and offers a slight protection against modern units. The City Defense is the Level 3 version, which protects against modern units too.