Taco Rex

So what do yall think the Spike is then? Until the whole "powerful artifact" thing, I assumed it was like an electrum-Atium alloy that stole Youth. But is it really a Lerasium spike? Pure Lerasium supposedly steals all abilities (like strength, but not invested powers) so it wouldn't be granting metalluc arts. So maybe it's like a Koloss' spike that is used many times to grant a crazy high charge? Could it be an Atium-Lerasium spike that steals all Abilities as well as a metallic Power? Is it a offworld Godmetal? Could we be seeing an alloy of Trellium? Autonomy did influence Scadrial before Era 1 according to a WOB. Is it just a standard metal spike charged with some offworld Investiture? If so, what could you steal that would make it be called a "powerful artifact"?