In my IRL games, it's the responsibility of the attacker to remind the other people to get attacked; this came up frequently, since we haven't seen an Attack card whose effects aren't resolved immediately before.
On the other hand, online, it's very easy to forget that your opponent has this out and get totally hosed by it. Ouch.
But this card is so cool, before greening it can potentially help your opponent, but +3 Cards at the start of your turn, man, that's what made Wharf amazing and here it is again, just more lopsided. Building decks that focus around duration effects is now asymmetrical and it gave me that brain-hurt that Dark Ages gave me in the best way imaginable.
Do they have to put back their starting hand? Or is it the whole hand they drew and played?
They put back all the cards in their hand that they didn't play, so green cards and unplayed Actions/Treasures.