2 decks. Difficult. No redeal.
Aces are moved to the foundations as they become available.
The top cards of tableau piles and waste pile are available to play. You may build tableau piles down regardless of suit. Only one card at a time can be moved from pile to pile. When any tableaus are empty you can fill the space with any card.
When you have made all the moves initially available, begin turning over cards from the stock pile to the waste pile. You can move cards from the waste pile to the tableaus and to the foundations according to the rules.
There is no redeal.
The rules state that you can move only one card at a time. But as a shortcut, BVS Solitaire will allow you to move a full or partial build if there are enough empty tableau piles, because you would have been able to get the same result by temporarily moving the extra cards into the empty tableaus.