Eldritch Horror: Strange Remnants

No. Most expansion components are added to their corresponding decks or pools, but Mystic Ruins Encounter cards and Adventure cards are used only with Syzygy or the In Cosmic Alignment Prelude, respectively; otherwise, return them to the box. (Rulebook, pp. 1–2)

Before setup, draw one random Prelude card and resolve its effect immediately unless it specifies different timing. As an optional rule, the group may choose a Prelude card—or choose not to use one—instead of drawing randomly. (Rulebook, pp. 2–3)

During the Encounter Phase, an investigator on the space containing the Mystic Ruins token may encounter it by drawing and resolving the top Mystic Ruins Encounter card. The token marks the space indicated by the back of that top card and moves if the top card changes. (Rulebook, p. 2)

As an action, gain one Focus token; you may spend one Focus token to reroll one die while resolving a test, with no limit on how many tokens you spend for rerolls. You cannot have more than two Focus tokens. (Rulebook, p. 3)

You cannot look at the back of a Unique Asset unless an effect allows you to. Unique Assets are possessions, so they may be traded using the Trade action, and there is no limit to how many you can have. (Rulebook, p. 3)

No. During the Encounter Phase, you must encounter each non-Epic Monster on your space before encountering each Epic Monster there. Against a Monster with Physical Resistance, you also cannot apply bonuses to your dice pool except those from Magical possessions and Spells, although rerolls and dice manipulation work normally. (Rulebook, p. 3)