Please note that there were limited sale items that includes captains which cannot be presently found under Gen. Max section.
Also, even if a person resets their account, all of the gold units remain in their possession.
You can find CAPTAINS buy clicking "GOLD BARS" at the Top-Right of the game page. You'll see "GOLD - DEALS - CAPTAINS - UNITS" Click "CAPTAINS" there you can purchase with Gold Bars any captains you want. Keep in mind you want to pick the Captain with either High Attack or High Defense if that is your playing strategy.
Special Limited Edition Captains comes out every holiday sale by purchasing up above or by going to GEN MAX and clicking CAPTAINS. Battle Cry gives out a new promo code around the 15th of the month that helps you get free gold bars to help purchase a captain every month or use it for other gaming uses..
The Captains "Purchased with Gold Bars" are considered low quality because they only have control over a few Army/Navy/Air Force Units VS Waiting for a Enemy Wave 1 to drop and completing that as you have several hundred that your captain commands for your Army/Navy/Air Force.
As you are leveling up, at 5 or 10 intervals, A new low level Captain will unlock and you can add them to your collection. They are MORE Powerful then :Purchasing a Captain with Gold Bars because the prize is Commanding 450 Army Units as shown above.All you have to do is complete "Enemy Wave 1" to add them to your collection to be a valuable piece. As you continue to fight more Enemy Wave levels that captain will get stronger and stronger for each war. Keep in mind depending on your gaming strategy say your only interested is "All Army" or "All Navy", etc. Then only focus on completing only those captains to your collection. I hope this helps you.
Thank you for your feedback and input, duly noted.