Fiendish Duo and Angraths Marauders will enable your sources to deal double damage to opponents
If cards are removed from your graveyard after that point, such as by exiling Jack-o'-Lantern from your graveyard to pay for its mana ability, this won't affect whether you can legally cast Graveyard Shift, even if that reduces the number of mana values in your graveyard to below five
You can also use it in reverse, putting a shadow counter on an opposing creature and making it unable to block anything without shadow
For cards under $1,000, platforms like TCGplayer, eBay (with seller protections), and local card shops are viable options
Instant Common Eduardo Francisco null/null LEGAL Standard LEGAL Future LEGAL Historic LEGAL Timeless LEGAL Gladiator LEGAL Pioneer LEGAL Explorer LEGAL Modern LEGAL Legacy LEGAL Pauper LEGAL Vintage NOT LEGAL Penny LEGAL Commander LEGAL Oathbreaker LEGAL Standardbrawl LEGAL Brawl LEGAL Alchemy LEGAL Pauper Commander LEGAL Duel NOT LEGAL Oldschool NOT LEGAL Premodern NOT LEGAL Predh Target creature gets -1/-0 until end of turn
