The way I've been playing the Ostheer, I call in the Tiger I or Elefant usually after the support armor korps is built while in phase 2. In the recent patch, you need Battle Phase 3.
I was thinking of a change: The Tiger I or Elefant call in requires same less CP than pre-patch but also requires Battle Phase 3 to be activated and either a Heavy Panzer Korps or Support Armor Korps to be built. That way, you need one main armor producing structure and it can be the one that call in versatile tanks or specialized vehicles.
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