I actually dont think that General Kreat offers much as a commander, but shell go great in the 99 of decks such as Krenko, Mob Boss or Purphoros, God of the Forge that are already looking to throw massive amounts of tokens onto the battlefield to finish off opponents
(They get +2 while challenging.) GO GET EM Whenever this character quests, chosen Alien character gains Challenger +2 and This character can challenge ready characters this turn
This card could win the award for the most metal-looking creature going, in both a literal and nonliteral sense, and is a three-mana 1/2 artifact creature with flash and flying
Just keep in mind your budget and the fact that you can more slowly accumulate gold that can purchase extra packs and cosmetics, if you have the patience
This may be a slow progression for the game to take so many turns to increase your mana and it may be easily disruptable, but its well worth doing in some situations