[This is Obama's illegal law.]
Fun Fact - Executive Orders are not laws.  While they both carry the force of law, ie. the authority to be enforced over objections, it is far more limited.  Remember laws, or legislation, can only be created by the Legislature and in some cases by the Judiciary, commonlaw, but never by the Executive.
Also, DACA functioned within the INA's (legislation) explicitly provided for prosecutorial discretion.  It is this same discretion that Trump relied on when he said he is deporting criminals first.