I started my nations to United Stated and switch to Iran to check if the energy really runs fast.. Its only 7 seconds faster and decided to switch to United Kingdom for sea power boost and increases defense.. You know what my best Indestructible 10th event unit switches, from Elite Heavy switch places to Fortune Carrier as my #1.. If you switch nations for example, Russia has the air power boost so your best air unit will show as the top 1 spot on your top 45 when u attack in PvP...