It gives us a sticky threat that is immune to sorcery-speed wipes like Deadly Cover-Up and continues to pressure the opponent even after our hand is empty
You cant quite do that with The Master, Transcendent, but this is a great tool to cheat out creatures with powerful abilities ahead of schedule
The more expensive the enchantment, the harder the dilemma: Take a chunk of damage each turn, or opt out by sacrificing that permanent
Also, since the overall power level of Modern is dramatically lower compared to Legacy and Vintage, the 2 for 1 for countering a medium-power non creature spell is often not worth it
The more artifacts you play, the bigger these constructs get, and nobody has that many board sweepers to deal with them all
For two and a Black, Phyresis Outbreak gives every opponent a Poison Counter and then gives every creature your opponents control -1/-1 for each Poison Counter they have