I have a suggestion, which could both make that off-map strike more attractive for people and make it way more realistic = more attractive again.
I think everyone, who played in CoH 1 remember V1 off-map strike and how it worked. For those, who didn't, I'll remind: 1 shot, long time before strike, that creepy annoying sound instead of flares, huge damage (insta-wipe of everything in blast area) and huge cooldown time. I think, that RailUberGun should work absolutely same. RailUberGun should be 100% similar to "V1" strike, but only in CoH 2.
And it would work good, I suppouse. That arty would be really good tool of 1-shot breaking UKF's emplacements, like it was with V1 and Emplacements in CoH 1. It would be really way better breakthrogh tool, than it is right now. And I suppouse, that that ability supposed to be effective breakthrough tool. Huge damage at once, but at least 5 mins cooldown, otherwise - people will abuse and spam it, like they do pretty often with Stuka Dive Bomb strikes.
And of course - it all will be more realistic. Only 1 powerful shot, destroying absolutely everything (look at pics of RailUberGun shell, it's damn bigger than medium tanks!), creepy sound also can be added and of course - long time reloading. It took hours, if I remember right to reload that machine - here is only 5 mins for you! Great offer, don't ignore it!
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So, what do you think about it? Im really sure, that such big instrument of making MASS DESTRUCTIONs, GENOCIDEs and Absolutely and Totally UNreasonable Ultra-Reich-1488%efficiency-VIOLENCE desreves to be better, than soviet kid size toy-howitzers .