For this mana (), you get two plain old boring 1/1 tokens (with appropriate tribal)

Bump it to and you can add a small ability (flying).

I don't know how much you'd have to pay for double-strike. Fencing Ace suggests you can can get one for ; so two needs to be a lot more - the exchange rate for "You only need one card" is at least on top of the initial double cost (as the plain token makers point out) - so maybe ?

for 7 mana, this will be unplayable. This is 1 card that puts 4 power and 2 toughness on the field. is 3 mana, common and instant.