The difficulty comes in sculpting a board state where you will get to play the Gambit for that effect, as you basically need to keep four mana up at all times
While Child of Alara is still a powerful commander, this 6/6 for WUBRG (One White, Blue, Black, Red, and Green mana) and its ability to destroy all nonland permanents upon death, isnt all that exciting
It is particularly strong in Limited, and I see the creature hit the battlefield (often through Sneak Attack effects or cards like Reanimate) in LSV's Vintage draft videos all the time
As a result, it may take a while to earn the in-game currency you need to build the deck you want
She could be my Commander from the set
These will be your creatures, sorceries, instants, enchantments, artifacts, etc