How to earn higher level flame tanks?

Get higher in operations.

Geden wrote:

Attention, General!

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• The day of availability is tied to the level of the Unit Card. Higher level cards are rarer, but also more powerful. For example the Flame Tank becomes available on the following days:
  • Level 1 -> Day 4
  • Level 2 -> Day 8
  • Level 3 -> Day 13

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Your Bytro Team!