It's a Boat, It's a Plane, It's... Just a Riverbeast.

Description
The Iron Horde swooped in when they identified a rogue submarine closing in on their stronghold. Unfortunately for them, it was just a riverbeast.

Counters

 * Gutshredder:
 * The Briny Expedition:

Rewards
You will receive:
 * Mudback Riverbeast