We all know and hate the Stamina bar. It is a resource that you have to ration and use wisely like any other.
Your stamina will gradually restore at a rate of 1 stamina every 5 minutes and if you click the bar under your avatar in the top left corner it will bring up the window that will allow you add more stamina. It will also highlight in green a timer showing how long it will take to regenerate to 120 stamina. It takes 10 hours to regenerate from 0 to 120.
While you can buy stamina to exceed 120 using gems and stamina items, you can only regenerate up to 120. I don’t know if there is a cap to how high your stamina can actually go, I never tested it.
The best way to spend stamina is doing rallies. This gets you maximum rewards and also rewards everyone else in the rally. Plus rallies earn the entire alliance gifts. In the Alliance Gifts tab there will be a list of rallies for which each member will be awarded a gift based upon the Alliance’s Gift level. Each click by a member will add 10 points to the progress bar. While that doesn’t sound like much, if all 100 members click claim, then that adds 1000 points. Claiming the gift will award you, at, for instance, gift level 21: 21 K food/iron/coin or 5 Gems or 10 VIP points. More rallies means more rewards to claim.
Every night before you log out, you should do rallies to clear out most if not all your stamina. That way, when you log back in the next day you will be at or close to your max of 120 and you can start all over spending stamina.
The best time to spend Stamina is during Arms Race Drone Boost. Do not waste Drone Battle Points or Drone Parts for that, save them for VS Day 1. It takes 15 rallies to get all 3 chests in the Arms Race. With all 3 squads, that can be done in a little over 5 minutes. If you start out with 100+ stamina, then first buy more using gems: spending 300 then 500 to get all 300 stamina needed for the 3 chests. Save your Stamina items for events like Zombie Invasion or Wars.