Some of these effects are good because theyre cheap
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The common theme with the companions is that all bar a couple of cases are only worth running in a cube if you can have some expectation of having them as a companion
Cards that dont require additional mana, like Sigardas Splendor and Cosmos Elixir solve this, but ultimately are a touch unreliable, especially in light of other card draw options in white
Well, in all honesty, the answer is that Wizards already have the rest of us hooked
Meanwhile, Caravan Escort isn't quite as efficient but still works really well with Time of Heroes, since we can level it up once, and then with the +2/+2 from the enchantment, it ends up as a 4/4, which is a pretty reasonable attacker on Turn 3