Then just Eeek at the beginning of your second turn.
Will that matter as much, though? You've had two turns to use Supporters and Trainers by that point, and if you've gone first your opponent still has only had one turn. Given the history of Pokemon, smart money is on aggressive decks.
Especially if your opponent opened with a
Cleffa, since it will obviously be awake. The donk has been most likely averted, but I think this would radically shift how the game is played. If you try to keep using
Cleffa or
Pichu for set-up, half your openings are going to be "Go second, start with an effective one-Prize deficit".
I'll say it again, but isn't it overall just as effective to require a player have two Basic Pokemon in play to open the game (and avoid a mulligan) than make such a special rule? In the current format it is indeed possible to "donk" someone first turn who started with two Pokemon by having both a second Pokemon of your own to "bounce" and a
Seeker, on top of whatever else you need to pull off the actual OHKO. That isn't as easy as it sounds, though obviously actual donk decks will pull it off.
Here's the thing: altering the game so you can't attack first turn for either player is going to make things more complex for newer/younger players, and devalues "set-up" attacks to the point I don't think they'd remain competitive, barring a
Twins intensive build. It would reduce donks, but not enough for the complications it introduces.
Oh, and once
Seeker is gone, unless another first turn bounce or damage counter placement card (potent or simply easy to SPAM) is introduced, the "double basic to avoid mulligan" change does eliminate the first and second turn donks.:thumb: