Blitz is a one-time only ability of a unit to operate during the same round they came into play.
How it works
If a unit has the Blitz ability, then they can operate (move / attack) during the same round they came into play. You can operate the unit any time after deployment until the end of the round as long as you have enough Kredits to cover the operation cost as marked on the card.
This means for infantry units that they can get deployed, then move or attack during the same turn. For tank units, this means they can get deployed and, then move and attack during the same turn.
For example, the Akita Regiment costs 2K to deploy and 1K to operate. This means you need to have at least 3K to blitz with this unit (deploy and operate during the same turn).
Blitz applies only during the deployment round of the unit and cannot be used at a later round.
How to identify Blitz units
When you look at the card, you will see the word "Blitz" written beneath its image.
The story behind Blitz
Blitz was inspired, of course, by the German Blitzkrieg and represents fast attacks to gain an advantage on the battlefield.
Dev blog Blitz, Buff, Bling & Banter