Gold

Q: Can Pickpocket kill a Gold token?

Yes, but we see why you'd ask. The rules use a "NULL" system for values that aren't available, such as the Might of a unit that's been removed from the board. The unit is gone and the information is missing, so you can't do any calculations or comparisons with it (not even "is it no more than 1?").

That system could reasonably be applied to the costs of tokens, but we feel that results in unintuitive situations, like not being able to kill a Gold token with Pickpocket. After all, the token's not missing; it just doesn't have a cost because it doesn't need one. We'll be updating the rules to clarify that the cost of a token can be treated as 0 for all purposes.

Q: Can Pickpocket kill a Gold token?

Rumble, Hotheaded

187.5. A Gold gear token is a domainless gear token with "[Reaction][] Kill this, [E]: [Add] [A]."

375. If an event that a Replacement Effect applies to would be modified by the Game Effect that generated that event, or the results of that event would be modified by a Game Action from a linked ability that references the replaced event, the Replacement Effect will inherit those modifications. Example: Treasure Hunter reads "When I move, play a Gold gear token exhausted." A Replacement Effect that says "if you would play a token gear, play that token and an additional copy instead" is applied to the event of the Gold gear token being played. The additional copy will also be exhausted, as it inherits the "exhausted" modification. Example: Another Replacement Effect says "if you would play a token, draw 1 instead." The modification from Treasure Hunter's ability cannot apply, so we ignore it. Example: A spell reads "play a ready 3 [M] Mech token. Then do this: Give it Temporary." A Replacement Effect that says "if you would play a unit token, play that token and a 1 [M] Recruit token instead" is applied to the event of the Mech token being made. The Recruit token enters ready and is given Temporary.