Evil Blueprints were added in Beta 36.0 as one of the cards using the new mechanic of "choose one" effects, and the first one to show it off due to being revealed on Twitter beforehand (and as 2nd of 5 total), as seen here. Previous Versions can be found here.
Since Beta 56.0, when the turn this is played ends, a (now Token) Thrashing Machine will be added to your hand, which is an effectless monster but still has ATK and HP above its cost, at 4/4 for 3G, while also having the benefit of being a part of every Tribe.
More detailed info can be found on Thrashing Machine's own page.
This makes Evil Blueprints a very valuable card for any deck that involves one or more Tribes, alongside the Evil Plan Artifact.