This is by no means exhaustive but is a taster for a more thorough tutorial to come later, so please use it as a quick guide to which officers to develop, for what uses and which skills. Remember not to develop too many officers at a time (ideally 1 or 2 at a time to level 50 and 5 star then move on).
But remember that Legendary officers need gold stars and these are hard to collect for free.
Remember to make sure you have Legendary (gold star) officer with 5 hearts in the appropriate positions in your base (this is the annoying card game).
Below is a quick list of the best officers and which Talent columns to develop:
Tank Officers
Combos:
Tank Destroyer Officers
Combos:
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