For Omega Supreme, it says once your opponent shuffles their deck you combine. If I swing with one of Omega's pieces, but mid-attack my opponent shuffles their deck, do I combine and stop my attack because the character who triggered the attack isn't and my opponent has another character untapped? Along the same lines, when someone attacks into an Omega Supreme piece and they shuffle their deck. When you go to combine, does the attack still go through to the now combined Omega Supreme? Or does the attack get canceled as the original target isn't on the field anymore?

If a character attacks or defends, and in the middle of the attack, combines into another character, the new combined character continues to attack or defend. Note that the combined character is untapped and will remain untapped for the duration of the attack.

Source: Wizards of the Coast (2019-11-09)    【Link to Ruling】

Tags: Combiner