Ruins
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When a well-known town on Loka dies, it becomes a ruin. While inside a ruin, some blocks will crumble and plants grow over time. Loot bundles and ghosts will spawn in ruins. There are 6 achievements for ruins.
Ruin Achievements
Lost Civilizations I - Discover a ruin.
Lost Civilizations II - Discover 5 Ruins.
Lost Civilizations III - Discover 20 Ruins.
Ruin Hunter - Find all active ruins on Loka.
Dark Ruins - Discover a ruin in a red infested tile.
Lost Loot - Find a loot bundle within a Ruin.