Further Explanation

Even in this new set. Horrendous Growth is build-around. Something like Deathmatch Pavilion demands you have weapons which Shamans have none of in the Basic set, and which they can have two of in a deck in the Classic set (Stormforged Axe). Rogue is more reliant on combos than Paladin which is why Time Out! is Common while Cloak of Shadows is Epic; it's easier to succeed as Paladin with a card that protects you from damage than it is with a card that prevents you from being directly targeted as Rogue. Immune has synergy with Paladin's weapons (Including Truesilver Champion and Rastakhan Rumble's other Common, Bloodclaw), and can be played at any point to stop damage, whereas Rogue would probably want to save the Cloak for specific turns a la how people sometimes used DK Valeera.

But continuing on. Occult Conjurer requires you to have Secrets. ***There are no secrets in the Basic set.*** For any class, let alone Mage. Imagine how shitty it would feel to unpack that card when it has ZERO workable synergies. Same with Jewel of N'Zoth in Hunter. No Basic Deathrattles! Even Loothoarder is a Classic card that needs to be unpacked.

Don't Feed the Animals requires you to have beasts, which there are 20 of in the Basic set for Hunter. But you also can't just slap beasts in a deck and call it a day. A deck that's RUNNING Don't Feed the Animals needs to have more of plan than "oh i'll get a handful of beasts and buff them with the +2/+2!"

There's also Epics from previous sets people were upset with because they didn't seem complex, like Primordial Glyph. But Glyph still requires you to have something of a game plan. It still requires you to know how to use the spells you work with, which themselves could be Epics you play suboptimally like Power of Creation or Pyroblast. ***The logic Team 5 has CONSISTENTLY gone with is, "How easy is the card to play/use on its own?"*** That's it. You can disagree but that's always been it.