While the card combination may seem convoluted, about 1/2 of the deck fills one of the requirements, so you will stumble on this combo very easily
Mold Adder Mold Adder is a 1/1 fungus snake that grows stronger whenever an opponent casts blue spells or black spells, allowing you to put a +1/+1 counter on it
But now, after a year in open beta, Magic: The Gathering Arena is out
So, for example, you may have 17 one-mana creatures, 77 two-mana creatures, 123 three-mana creatures, 113 four-mana creatures, 80 five-mana creatures, 42 six-mana creatures, and 30 seven-mana creatures
As written, you can cast cards anyone plundered if your plunder value is high enough, but it would be easy to limit everyone to their own plunder stack