Rule 832.1.c.4
If some or all of the [Object] set leave the appropriate zones during the finalization process after being shown off, it will not prevent the source of the Show Off ability from becoming a Finalized Chain Item. Example: A spell reads “[Show Off] a Mech” and “As an additional cost to play this, discard 1.” When finalizing the spell, the same Mech being shown off can be discarded to the mandatory additional cost without preventing the spell from being finalized.