when this case enters the battlefield, investigate. (create a clue token. it's an artifact with "2, sacrifice this artifact: draw a card.")
to solve — you control three or more artifacts. (if unsolved, solve at the beginning of your end step.)
solved — 2u, sacrifice this case: put four +1/+1 counters on target noncreature artifact. it becomes a 0/0 bird creature with flying in addition to its other types.