Instead of just aiming to deck an opponent out, mill payoffs let you turn every lost card into an advantage that pushes you closer to victory
-1/-1 Counters -1/-1 counters are more uncommon than their brother, the +1/+1 counter
Giant Growth is the oldest and still one of the best Pump spells in the game
Even within the rules of fan-art I listed above: people buying it know theyre buying a proxy, a replicated card (at least, assuming its not someone trying to hock a proxy off as being authentic) the fact that it does use authentic artwork is tricky, and maybe the most grey of greys involved proxies dont interfere with the rights-holders from selling cards because, well, the rights-holders dont get ANY money from the secondary market to begin with
Stay updated on trends and consider revisiting your collection regularly to assess its value and potential growth
Granted, there are similar cards like Ashnod's Altar that dont require you to tap it