Related Clues:

• Middle of the Rockies
• Lizard
• ___ monster
• Colorado feeder
• River to the Colorado
• Tributary of the Colorado
• Type of monster
• Monster lizard
• The Painted Rock Dam blocks it
• Monster or River
• "Monster" that's really a lizard
• Southwestern river
• Sort of monster
• Monster type
• Black Canyon carver, with 'the'