Notice that the second part, while limited to your first attack, is not limited per player that's to say, if you manage to hit all three of your opponents during your first attack, you get three extra attacks
If possible, you want to be attacking with your Slash Dragon (Ideally into a repeatable destruction threat like Hand or Frost/Flame) to get it equipped with the Gearfried from its effect for an additional negate and to build up PotG
Save your money on Silver Tempest Pokemon TCG Live codes and buy in bulk, it will slightly lower the price per code
The two alternate password cards (plus the gift for Hajime Syacho) are also listed separately in the wiki, including most of its subpages
In Standard, slowing down Screaming Nemesis and Emberheart Challenger is essential, and Authority of the Consuls does the job