Lightning Strike feature is one of the features that allows you to progress through the Season and collect rewards to climb to Tier 5 and qualify for the Leaderboard.
More information about Leaderboard is here - https://productmadness.zendesk.com/hc/en-us/articles/360021852651-Seasonal-Leaderboards
Feature's icon is available in the Game Lobby and you need to click on it to open the feature's view.
The tasks that players are required to complete to charge their Daily Charged Reward are listed on the screen. There also are feature's rules, timer and 7-Day Chase levels.
The Lightning Strike and 7-Day Chase feature last 5 days and you are required to complete at least 6 tasks daily to charge the reward and claim it the next day, and progress through 7-Day Chase orb levels.
Please note, you do not earn the orb as soon you reach each level. You only get one orb reward each week, on Saturday. That progress bar just tracks what your reward will be at the end of the week. With each completed set of daily tasks your orb level will be increasing.
As soon as LS tasks are completed and rewards are claimed main reward is charged, so you just need to wait until timer resets. Then you will be able to collect your Charged Reward! Usually the following day.
When it's time the pop-up appears on your screen and now you can claim your awesome reward!