In those four ruin cards, real treasures are hidden…
Imperial Settlers: Ruins consists of four different common cards, each in one copy only. All resemble the base game Ruins common card (COM074) with the only difference being that cards from this expansion provide other resources in their building bonus than the base game Ruins card:
RUINS001 — Watchtower Ruins: defense token
RUINS002 — Armory Ruins: raze token
RUINS003 — Temple Ruins: victory point
RUINS004 — Town Ruins: two workers