The most powerful website at your disposal is Moxfield
Intent Fan-made: creative expressions by fans who want to play with the card design rules Proxy: functional placeholder for existing cards, such as cards they want to play with but are out of reach for them Counterfeit: deceptive cards for profit Presentation Fan-made: clearly unofficial, such as making cards for Fakemon or adding new types Proxy: obvious stand in, many will even just outright say this is a proxy card Counterfeit: designed to look authentic in order to fool buyers and collectors Use Case Fan-made: to show off creative works, gameplay ideas, or just for having fun Proxy: testing or casual play, usually in decks and if allowed by other players Counterfeit: resale and fraud, tricking buyers into thinking its authentic product Likelihood of Confusion Fan-made: low, as usually artists will sign their own names or the cards will denote who designed the blank template used Proxy: low to moderate, usually proxies will not only say this is a proxy but may also have a different card back to further reduce confusion Counterfeit: high by design, they will replicate the card layout and back as close as they can Legal Risk Fan-made: low, fan art tends not to be legally persued Proxy: low to medium, proxies may risk confusion with authentic product, but proxy makers can mitigate that by clearly stating its a proxy Counterfeit: high, as commercial counterfeiting is illegal For what its worth, there is definitely a lot of crossover
Even if the Subterror monster you control is flipped face-down by some other means or is removed from the field by any other means, the negate will still resolve
While precons are generally weaker than decks created by players, Mutant Menace is strong enough to hold its own without any alterations against non-precon decks
