Now that the Lvl 5 silo is available, wouldn't it be rational to allow the Lvl 4 upgrade for the PH9's ? Having the last 2 silo upgrades both on lvl 10....isn't it weird? Just my point of view. Peter
I also found this odd. I believe it was similar that PH9 was required for both of the two final fort levels, rather than letting one be PH8. I believe the biggest reason for this is how much HP it has at level 4 is balanced for a PH10 island, and giving that much extra HP at PH9 would unbalance things a little bit (I forget how much silo 3 has, but silo 4 has a lot of HP, so I'm guessing that HP upgrade is probably the biggest reason). It would be nice to extend the silo 4 upgrade to PH9, even if the hp had to be cut until silo 5 to compensate for the earlier unlock.