There is no mulligan. Player 1 always goes first. Player 1 is always at the bottom.
Lots of cards aren't working. Xros and DNA are completely missing. Cards from the preset decks you can create should work (with some bugs).
You can compose a challenge to give to your friends. Helpful for learning those weird edge cases.
On Discord for now invite link
Say stuff you want, there's a suggested list of requests down below
If you try to break the software by messing with the inputs you'll succeed and it won't be interesting. If you breaking the game logic by playing a weird set of cards, that is interesting.