This is not your typical Lego creation.

A mysterious masked maverick is brightening up a drab retaining wall at the base of the Wainuiomata hill, in Lower Hutt, with giant spray-painted Lego blockheads.

The location is not exactly the kind an artist looking for exposure might choose to canvas, but this artist said he was not in it for the recognition.

"As an artist you kill for exposure. It's quite cut-throat in the industry. But I want to keep it anonymous. For me, it's more about the community, less about the artist.

"I'm crowd-sourcing all of their ideas and trying to make their visions happen I've had some wonderful stories from people about how it's impacting them positively, it's awesome," the masked man said.

Having no council approval, he admits he was nervous about his first block - the simple yellow Lego face - but decided instead of being stealth, the best way to execute it, was to hide in plain sight.

"I came in, in the middle of the day, put a hi-viz on, put a couple of cones out. I gave myself a pretty strict timeframe - 10 minutes - so it was very quick but now I find I can be here for a bit longer and the community is very supportive and I'm not so worried."

Hutt City councillor Josh Briggs, who is helping keep Blocksy's identity under wraps, is also helping facilitate the many offers of help and donations that have started to pour in.

He said this was exactly what the people of Wainuiomata were all about.

"The community's imagination and creativity is just really hyped at the moment, and everyone's just waiting for the next piece of art to appear to take in and enjoy. We're really lucky to have such an amazing local artist putting their work out for us all to see and enjoy."

The artist has gathered more than 2500 Instagram followers under the handle block_vandal_ since setting up the social media account just over two weeks ago.

The account showcases the art already there - Spiderman, the Hulk, Nick Fury, wonder woman and more.

So when will it stop? Blocksy hoped not until the whole wall was done.

As for Blocksy's identity, it'll remain a mystery, for now.

"I think at this stage, I'm taking it day by day.

"I'll do my best to keep this project as exciting for the community as possible. I think the anonymous part of it is something the community really enjoys so I'll probably hold onto hat for as long as I can... You may never see me... [laughs]."