For one, theres better Horrors out there you can stick in their place but theres also not a ton of reason to be this all-in on Horrors to start with
Whenever one or more creatures deal combat damage to you, each opponent sacrifices a creature of their choice that dealt combat damage to you this turn
Beyond that, it's sometimes better to scrap an artifact for a more useful one that happens to be cheaper
and with additional copies of [casthaven]Riptide Chronologist[/casthaven], you can probably drain someone down from 21 or even 40 life out of nowhere
At least, you should with a card that has such high combo potential
As long as expectations are there, the price will be there, and thats all we need to care about on a spec like this