Gallery and List of Poison Cards In addition to cards that have infect or toxic, these are cards that can put poison counters on a player: Crypt Cobra Sabertooth Cobra Suq'Ata Assassin Pit Scorpion Marsh Viper Swamp Mosquito Serpent Generator Hand of the Praetors Ichor Rats Relic Putrescence Virulent Wound Pistus Strike Decimator Web Caress of Phyrexia Reaper of Sheoldred Fynn, the Fangbearer Ajani, Sleeper Agent Norn's Decree Phyresis Outbreak Prologue to Phyresis Infectious Inquiry Vraska, Betrayal's Sting Vraska's Fall Infectious Bite Etali, Primal Conqueror Etali, Primal Sickness Persuasive Interrogators Bloodroot Apothecary Virulent Silencer There are other cards like Corrupted Resolve and Mycosynth Fiend that mention poison counters but don't actually distribute them
If a cost includes causing you to gain life (like the alternative cost of an opponent's Invigorate does), that cost can't be paid
If you wanted extra cards playing mono green there were usually drawbacks like needing an artifact that benefited all players, such as Howling Mine
Players would split the deck and play to see if the core rules actually worked
It's also theorized that early Pokmon players may have been prejudiced against the pink, nurturing Chansey Pokmon, and may have taken less good care of the card than they did with favorites like Charizard or Venusaur