When Svellsongur is attached to Aphelios for the first time, how many times does it trigger?

When Svellsongur is attached to Aphelios, Exalted for the first time, it triggers twice.

According to RiftJudge FAQ #541 and #8411:

1. Attachment and Copying: As Svellsongur attaches to Aphelios, it copies his printed text. This grants Aphelios a second instance of his triggered ability.
2. Triggering: Because the copied text becomes active during the attachment process, both the original printed ability and the newly granted ability trigger simultaneously in response to the equipment being attached.
3. Resolution: Each instance of the ability is independent. The restriction "choose one that hasn't been chosen this turn" applies separately to each instance. This means you can choose the same mode for both triggers, or different modes, as long as you track the choices made for each specific instance of the ability.

Sequence:

• Svellsongur is attached to Aphelios.
• The attachment event triggers both the original ability and the copied ability.
• Both abilities are placed on the Chain.
• You resolve each trigger independently, allowing you to make a choice for each instance.