*2nd tier (terrain)* **Challenge** 6 (2,300 XP); **DC** 16/14 **Area** Local (1 hour) The lake ahead is an eerie and unnatural green, and when gazed upon in the night it glows. Algae has turned the water this color and the fish living within it have adapted to have no eyes. #### Dangerous Algae A [[03-Mechanics/6-Ability Scores/Nature|Nature]] check identifies the type of algae as a poisonous variety, making the lake water dangerous to touch. Deliberately drinking or trying to swim across the lake triggers a **Critical Failure**. #### Harvesting A [[03-Mechanics/6-Ability Scores/Medicine|Medicine]] check reveals that the algae can be dried out, at which point it is no longer poisonous and can be used as a clotting agent (functioning as an [improvised bandage](https://a5e.tools/rules/medicinals)). ## Possible Solutions The party can make a group [[03-Mechanics/6-Ability Scores/Athletics|Athletics]] or water vehicle check to cross the lake by boat or raft. At least one adventurer must be making a water vehicle check; otherwise all [[03-Mechanics/6-Ability Scores/Athletics|Athletics]] checks have disadvantage. If they do not have a water vehicle, one adventurer can spend 3 hours to build a raft with an [[03-Mechanics/6-Ability Scores/Engineering|Engineering]] check. **Critical Failure.** The boat capsizes and the party is plunged into the green water, losing half their Supply Dice. They each gain a level of fatigue, and are poisoned until they take a long rest. **Failure.** The adventurers boat across, but they encounter a mishap, losing 4 (1d6+1) Supply Dice. **Success.** The adventurers follow their route and cross the lake unhindered. **Critical Success.** The adventurers harvest useful things from the lake, gaining one use of a [healer’s satchel](https://a5e.tools/rules/medicinals) and 4 (1d4+2) Supply Dice. ## Leave It Be Bypassing the suspicious lake is possible but takes a while — safely traveling around it costs an extra day of travel time. **No experience** is awarded to the party.