There are four to choose from, so which is best for you and your playstyle
By bidding at auction you agree to be bound by these Terms of Sale as amended and supplemented, whether you bid in the room, through a representative, by phone, by internet, or absentee bid
A 5000-power Character you boost with two +2000 counters is effectively 9000 for that combat, then returns to 5000
To determine the total cost of a spell, start with the mana cost or alternative cost you're paying, add any cost increases, then apply any cost reductions (such as that of Mutated Cultist's second ability)
There are also people who say that their individual stores have already been enforcing this rule
62/102 Sandshrew