When using Diggersby's "Mining Rush" attack, can I discard cards one at a time or do I have to discard them all at once?
You may discard cards one by one for Mining Rush and stop any time before you reach the maximum amount specified in the attack. You do not have to declare up front how many cards you're going to discard.
Source: TPCi Rules Team (2020-05-07)

Relevant cards

Note: All applicable cards may not be listed below.
SWSH2_147
SWSH2_147