The 'particle cannon' card has been causing a few issues. I can soft-lock the game where the enemy has -HP but doesn't take a turn but isn't destroyed. The card doesn't seem deal damage when it's played but rather after another card is played, it also doesn't immediately get discarded and I can use it more than once--I think this has an energy cost but the indicator lamps stay lit. I can't target the ship if it has -HP but it can be destroyed if I play an area effect weapon like Napalm, provided I can target another ship.
Kind of a minor quibble but there's now a slight delay between when my cursor is over a card and when it will respond to being clicked on.