Its a perfect example of early Magic design what we would later label a top-down approach which tries to match the lore as literally and intuitively as possible, even if it makes cards harder to understand at first glance
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Personally, I generally wouldnt go over 18 creatures or below 13, but there are plenty of times I would go outside of this range, especially if a format has a particularly spells-heavy archetype
Emrakuls Evangel 2G Creature Human Horror 3/2 T, Sacrifice Emrakuls Evangel and any number of other non-Eldrazi creatures: Put a 3/2 colorless Eldrazi Horror creature token onto the battlefield for each creature sacrificed this way
The card pull is random, but you can see what the pack contains before you choose
Clearly these mass removal cards were for decks with almost no creatures