Layering in mech spectre adding might to ferrous forerunner get switcheroo

There's no card named "Mech Spectre" in the Riftbound database, so I can't give a card-specific ruling. If you meant a passive effect like "Your Mechs have +1 Might" (e.g., Rumble, Scrapper), here's how layering treats it:

That kind of effect is a static ability applied in Layer 3, Arithmetic (Rule 477.3) — not Layer 1 (setting Might) or Layer 2 (granting keywords). Since it's a passive, it applies each time layers are evaluated, so it also boosts Ferrous Forerunner if he's a Mech. Increases are applied before decreases (477.3.e.1), and if multiple +Might effects hit the same unit in the same layer, you resolve dependencies first, then timestamp order (Rules 478–480).

If "Mech Spectre" is actually Mechanized Menace (legend: "Your Mechs have Shield. +1 Might while they're defenders"), then Ferrous Forerunner gets the +1 only while defending — still Layer 3, conditional on defender status. Let me know if you meant a different card and I'll re-check.

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