Deal - Standard 7 card stud setup (two down one up).
Offer up cards
Dealer reveals a card from the deck and offers it to the next player
The player can buy the card for $COST or take a free card from the deck
An unclaimed card is offered to the next player
An unclaimed card at the end of the round is discarded.
$COST =
Round 1 = $0.10
Round 2 = $0.20
Round 3 = $0.30
Events
Natural Pair of 2s - Deal another (free) face up card. This cannot produce an additional event.
Natural Pair of 3s - Select an up or down card in another players hand and discard without revealing it.
Natural Pair of 5s - Select an up or down card in another players hand and add it to your hand. Cards taken this way cannot create another event. I.e. stealing a 2 from a player when you have a 2 showing will not create a Pair of 2s event
Hole cards never generate events
Events are resolved once when the card that causes the event is revealed.
Once a card has generated an event it cannot create further events. e.g. revealing a card that causes 3 of a kind would not trigger another pair event.
As usual in seven card stud, players are dealt two cards face down (hole cards), four cards face up (table cards), and a final one face down. The cards are dealt one at a time, and there are five betting rounds: one after each round of face up cards has been dealt and one after the final round of face down cards is dealt.
https://www.pagat.com/poker/variants/invented/stud.html#trainwreck