Which promo cards are permitted in Constructed tournaments?
[Source: WotC] 
We were having a debate at the local draft on when cards such as Bumblebee - Trusted Lieutenant says: When this attacks -> You may scrap an Action from your hand. If you do, draw 2 cards. Our question is about flipping. Is tapping to attack put the flip cards on (basically all Transformers state: When this attacks/or defends -> flip 2 battle cards) This isn’t stated specifically in the rules, but with cards like Dinobot Snarl allowing you to plan 2, you could very easily want to flip then place 2 defensive cards on top (or if you utilized Plan prior to the attack). We have all been playing it is before the flip, but since it isn’t stated anywhere that we could see officially, we’d love a clarification.
[Source: WotC]
Any ability that just says “When this attacks” and doesn’t look at what you flipped happens before you flip battle cards.
Would playing multiple instances of
Steamroll in the same turn allow for damage, if it were high enough to KO the second character as well as the initial character that was knocked out, to carry over to a second or third target? For example:
Brainstorm into two Steamrolls or play Steamroll and then flip Bumblebee - Trusted Lieutenant into alt-mode and play a second or even a third Steamroll (if Brainstorm was played first).
[Source: WotC]
Playing more than one instance of
Steamroll on the same character has no additional effect. The extra damage will carry over only once.
When you attack and scrap an action, what happens first: the draw two or the attack flip?
[Source: WotC]
If you’re referring to the Bumblebee - Trusted Lieutenant’s bot mode ability, you would draw two first. Attack abilities happen before flipping unless they’re related to the flip.
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