Findings:

• Grumble
• grumble and grunt
• Grumbles from the Grave
• Grumble (user)
• SA-10 Grumble
• grumbles (user)
• SA-N-6 Grumble
• mumble
• Mumble something crazy
• Mumble (user)
• mumble some magic words
• Count Dracula has dyscalcula. He mumbles numbers and never slumbers.

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