representation of a Godzilla-like urban monster, used in urban/housing advocacy (by various parties with various meanings!).
Plaza 16 Coalition - "Monster in the Mission" 
The earliest attested use was reference to a "monster of development" in Mission. Tweet from Plaza 16 Coalition, May 16, 2014
Plaza 16 Coalition, organized against the proposed project from Maximumus at 16th & Mission Sts, adopted "No Monster In the Mission" as a sloan in 2014 and has used it since. Twitter hashtag search link: #NoMonsterInTheMission.
Plaza 16 Coalition graphic from 2014:
Plaza 16 Coalition poster from 2016:
Alfred Twu - NIMBY and YIMBY monsters 
originally drawn by Alfred Twu in response to "Monster in the Mission" motif used by Mission activists to oppose project at 16th & Mission. We think the first published instance was "The Real Housing Monster," reprinted in SF Examiner column by Joel Engardio on Feb 15, 2015.
SFBARF / SFYIMBY mascot 
After Alfred Twu's "NIMBY monster", he drew variants which suggested a positive YIMBY / upzoning monster. It became an often-used motif and avatar for SFBARF (YIMBY org) and SFYIMBY.
Chad Crowe - Urban Zilla
On August 22, 2019, Seattle-based Christopher Rufo, a former political candidate and now editor at City Journal, published an opinion piece "'New Left Urbanists' Want to Remake Your City" in the Wall Street Journal. It was accompanied by an illustration of a Godzilla-like creature, created by Chad Crowe, of Portland, Oregon.
Crowe's illustration immediately proved higly popular with urbanist advocates of all kinds. It was dubbed TOD-zilla -- referring to TOD Transit Oriented Development" -- by Andrew Small https://twitter.com/asmall_word/status/1165090769431977985?s=20, and Upzilla by @ne0liberal https://twitter.com/ne0liberal/status/1165376756397854720?s=20.
Crowe is now selling products featuring the artwork at: https://www.redbubble.com/people/whitecap73/works/40997971-urban-zilla.
- Engardio, Joel. "A Monster Mash to shock us out of SF housing crisis." [column]. San Francisco Examiner, Feb. 15, 2015.
- Ruffo, Christopher. "'New Left Urbanists' Want to Remake Your City." The Wall Street Journal, August 22, 2019. https://www.wsj.com/articles/new-left-urbanists-want-to-remake-your-city-11566512564.