Darkstar, please show me how YOU fight with iron age units there
I'm fairly sure that says you can fight with units from any era, not that you'll win no matter the units of your era. Let's not ignore the part of the announcement which clearly says this is mainly aimed at advanced players. Though of course, unlike with other GvG maps, lower-era players can still help you out here.
How so? Well, for one the required resources are not goods of specific era, but medals, which a player can access in any era. At the same time there are multiple ways they can help you without directly going against FE units. They can start sieges with their own units, and they can place defending armies. The later can be utilized quite skillfully because if you have 1 defending army with FE units and 7 defending armies with IA units the sector building/image will be a FE one, and at the same time since you cannot see the defending armies till you actually attack a sector, this appears as a sector protected by 8 FE armies
(you can also use it as a temporary solution till you actually replace these armies with higher-era units).
Of course you can try attacking a sector and see what armies are actually defending it. If the guild has placed lower-era defending armies, you can have your own lower-era players help out take over the sector faster. So, even IA units can be used to win battles.
and now I tell you how it made correctly (found that solution in minutes. you had month for your version):
the defending units are in the age of the attackers unit (= the PvP tower in which it would count)
how would that work:
the units are categorized by the type not the exact unit
for example: 2 heavy, 2 fast, 4 artillery
and if I make a late middle age fight those 8 units would be from that late middle age
someone else attacks with Future Era units. and he would get those 8 units from future era
to make it more challenging and balanced for all: all fights could be without any boosts
that would be a Free for All I would love.
While I understand the idea, and it's one of few alternative ideas that I myself have been pondering over when this was introduced, you have to realize that not everything that works on paper will be feasible for the game. What you're presenting is a very complex and resource consuming idea and even if it can be done (which would take a lot of time and work) it may not be compatible with the game itself. It may not work at all, or there may be too many technical difficulties for it to work properly.
Now, that's not for us to decide, it's up to the development team to figure out what can or cannot work so all we can do here is pass along the feedback. But you need to keep an open mind that even though some ideas sound good, they may not work well in practice. And of course, you may have seen other games with similar mechanism, but the background is not necessarily the same as all programming languages are different.
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Thank you all for the feedback so far, please keep it coming. I would kindly ask you that we try and focus on what we believe can be changed to improve it. While it may mainly target advanced players, hopefully with some tweaks it can become more inclusive of lower-era players.