Doppelgangers are aethers that are identical copies of Silver, Gold or Platinum customs. They are created with Doppel Charms.
Fusions can be created from any two silver doppelgangers, consuming them in the process.
Many users collect doppelgangers, and there are Trophies to signify how many you've obtained.
Silver Doppel Charm
Gold Doppel Charm
Platinum Doppel Charm
Legacy Doppelgangers[]
Legacy Doppelgangers are doppelgangers that were created before the fusion script was rewritten to create fusions from doppels instead of customs. Legacy Doppelgangers cannot be fused.
How to identify a Legacy Doppel