| Core Type | Armours / Weapons Usable With | Can be use instead of : |
| Low (FCL) | Aramid / Shadow Steel or lower | Nothing |
| Medium (FCM) | Titanium / Pherystin or lower | Low (FCL) |
| High (FCH) | Sigmetal or lower | Low (FCL) & Medium (FCM) |
| Highest (FCHH) | Mithril or lower (all Armour / Weapons) | Low (FCL) , Medium (FCM) & High (FCH) |
