Then I realized it is a fair 2 mana = 1 damage combo that is instead very difficult to deal with because Burning-Tree Emissary is always safe in the hand, Temur Sabertooth can get indestructible if you always keep 2 mana open and have another creature on the board and Outpost Siege is an enchantment
Will you fight the behemoths at your door, or fight alongside them?
If they die, get exiled or anything else that removes them from the board, you can instead put them back in the Command Zone, but you have to pay two more mana to cast them - and that cost goes up every time
This means that you'll reliably be able to continue to cast spells, regardless of how many cards are in your hand
Now Aberrant Researcher, he starts out as a 3/2 Flyer just like Insectile Aberration
The design philosophy of making a card that is as much about all the colors separate as its about them all together will never cease to be charming