With Chandra, Novice Pyromancer we wanted her to have a little more edge to her as she sets out to find herself on Ravnica
It's designed to play catch-up on all axes card advantage, life, and mana -- and hitting each opponent at once means you never have to choose which resource you're going after
When it comes to gameplay, Dragons are hugely powerful, and many Dragon creatures feature game-breaking abilities that swing games in your favor soon after they hit the board
He provides a full write-up plus code over on hackster.io
Assuming you're not a 5-color deck with a stringent mana base requirement, the only reason I see not to run Arena of Glory is that all your creatures already have haste
However, Foundations is slightly different to other sets, at least in terms of Standard