Mishra's Factory

{T}: Add {C}.
{1}: This land becomes a 2/2 Assembly-Worker artifact creature until end of turn. It's still a land.
{T}: Target Assembly-Worker creature gets +1/+1 until end of turn.

Dominaria Remastered

{T}: Add {C}.
{1}: Mishra's Factory becomes a 2/2 Assembly-Worker artifact creature until end of turn. It's still a land.
{T}: Target Assembly-Worker creature gets +1/+1 until end of turn.

Jumpstart 2022

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A noncreature permanent that becomes a creature can attack, and its {T} abilities can be activated, only if its controller has continuously controlled that permanent since the beginning of their most recent turn. It doesn't matter how long the permanent has been a creature. Notably, if you turn Mishra's Factory into a creature on the turn it entered the battlefield, you won't be able to then activate its first or last abilities.

After it becomes a creature, Mishra's Factory will still have all its abilities.