https://www.boardgamegeek.com/article/9523759#9523759
If both players end up with the same Priority, then they Clash. They can't change their style card. But both players select a new base card and place it face-down on top of the original base card. Once both players have selected a new base, they reveal their choices.
The new bases replace the old ones. Players calculate Priority as normal. If, after clashing, both players still have the same Priority, they clash again. They both select a new base and place it face-down on top of the previous bases. The newest base cards are revealed simultaneously and Priority is calculated as normal.
It is possible for players to keep clashing until they both run out of bases. Should this happen, the style and the last base cards move to the Discard 1 pile, discards recycle, no player activates, and players proceed to the next beat.
Once a clash resolves and one player has a higher Priority than the other, play proceeds as normal.
Only the last base card revealed goes to the discard 1 pile. All the rest of the revealed bases return to their player's hands.