A little extra space in a box is fine
On top of Krenko exponentially copying an army of goblins to control each turn, it's even better when paired with cards like Goblin Warhchief that let you get out the already cheap creatures for 1 mana less, while Shirk Prospector can sacrifice as many goblins as you want to generate mana whenever you need for a devastating attack, making you a threat for any matchup without consistent creature removal
Thantis, the Warweaver A lot of commanders are on this list because they incentivize quicker and more aggressive play, which can keep games from feeling overly long and boring
In casual games or booster draft, that sacrifice is deceptively easy to do, but the same may not be true in Commander, where decks have a much lower density of legendary creatures and artifacts
By Nathan Pynn An extremely rare Pokmon card that cost 2 (over $2) in 1999 has sold for a whopping 30,000 (nearly $40,000) at auction
otherwise, its risky