Blitzkrieg gives +3 movement lenght, +2 view range to units, but reduced the defence on all units by -2.
Blitzkrieg is good for rapid attacks. Blitzkrieg is the preferably stragety for players who are trying to make massive gains and aggressive attacks to win games. Blitzkrieg however is horrible for defence, as the only possible way to win defensive battles using blitzkrieg is to use a "flexible defense" where one willingly sacrifices cities but maintains a large offensiive force to regain lost territories immediately after they fall. Note passive players or players who need passive/defensive roles should not use this for scenairos. Blitzkrieg is intened for aggressive attackers who can raise large armies and outmaneveur the enemy. Also infantry are used more commonly for blitz due to their increased range.