gold core how tf do you get these

[Yoni]

deadass can someone tell me all possible known ways of obtaining these.. i have 50 cores of each other color but only 4 gold cores smh

[Kukiko]

Events or break down a million rare items. They sometimes have double chance to get gold cores from rare items so save your items till then. Also don't get those ugly devil wings.

[soldier king]

No cursing