Hi, these is common knowledge to many vanguard players (so don't flame me for speaking the obvious), but I thought of sharing it here for the benefit of players who never thought about this or is completely new to game.
There are a string of numbers that are good to remember when playing vanguard. 10-15-20-25 and 11-16-21-26. These strings refer to the various attack power levels a full single column(assumably 2 units, 1 to boost the other) can deal.
10-15-20-25: refers to various attack power output levels done onto an opponent's 10k vanguard. When your column's power is more than or equal (>=) 15k, the opponent needs a 10k guard, >=20k opponent needs a 15k guard, >=25k needs 20k guard.
11-16-21-26: this is against an opponent's 11k vanguard. When your column's power is >=16k, the opponent can no longer use a 5k guard, he at least needs a 10k guard. >=21k means 15k guard, >=26k needs 20k.
So whenever you make your deck, plan to at least strike a 10k vanguard for 15k, or preferably a 16k power against an 11k vanguard. And more importantly whenever you are planning to power up your deck by buying new cards, consider (assuming no other card effects) does the new cards' higher power push your column's total power into the next level (ie. from 16k to 20k into >=21k), if it doesn't and there are no other beneficial card effects from the new cards, perhaps you may wanna save your money
cheers. Of course, if anyone have more to add or different opinions, feel free to share