Heroes Alliance Monthly Mayhem is a monthly challenge comic hosted by Macattack. Every month a challenge is set. Despite the title, characters from both Heroes Alliance and Heroes Unite as well as related characters are eligible for use in the challenges.
- September 2011 - "Draw one of your heroes along with their name, and brief description of them. Entries by CPDX, Koikoi, Wes_Nero123, Fukujinzuke and Macattack.
- October 2011 - "Draw a villain. Bonus challenge: Write or draw a short story about your villain that can creep the reader out.". Entries by Fukujinzuke, Koikoi, SUX and Macattack.
- November 2011 - "What is a hero?". No entries.
- December 2011 - "Your hero must work to save Santa from ANOTHER user's villain!". No entries.
- January 2012 - "If your hero/villain had a different powerset what would it be and what would they look like?". No entries.
- February 2012 - "For this month's competition show your character falling in love with another HA character!". Entry by Macattack.
- March 2012 - "Choose any hero or villain from the HUniverse. Show how they would handle being stuck in a winter wonderland." Entries by Nepath and Abt_Nihil.
- April 2012 - "Draw any HA character pranking another.". Entries by Fukujinzuke and Irrevenant.
- May 2012 - "Somehow tie your Heroes Alliance Characters in with Star Wars". Entries by Irrevenant and Fukujinzuke.
- June 2012 - " Relive your school nightmares or just have fun drawing any HUniverse character stuck in school". Entry by Fukujinzuke. June also marks HA Monthly Mayhem's first cover page (which doubles as an entry by MacAttack).