It gives you the ability to get by at a table unnoticed until you've built up a terrifying board state
[casthaven]Duress[/casthaven] is the easiest, as it is great against control, Atarka decks, [casthaven]Retreat to Emeria[/casthaven], and Jeskai variants
Lots of drawing, mana, and stability make this a very solid color pair for combo
Your deck can only comprise cards of two different ink colours (Amber, Amethyst, Emerald, Steel, Ruby, Sapphire)
Unicorn and Equine Typal Its a flip of the coin which commander you use since the full synergies arent quite there yet
Standard also has two other creatures with this exact mana cost: Craterhoof Behemoth and Ghalta, Stampede Tyrant, which are much more proactive threats