+10 crit in exchange of +10 cost to units.
Each crit point gives +1% chances of doing a critical hit. Default is 5, with LB you get 15 (or 13 on some) as minimum.
A critical hit does more damage. A critical hit does the current roll plus max damage.
For example, your tank (normal tank. Attacking, therefore your max damage is 8) rolls 5, but does a critical and does 13 instead. 5(normal roll) + 8(maxdamage)
With upgrades and general, your infantry can get up to 19 crit, and that is why I love it so much
Ask Alex Meza
He is master for Lucky bastard. haha
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LB our best friend.