It can shut off or force the hand of cards like Krark-Clan Shaman and Skirk Prospector, though, and for two mana that's not a bad exchange
The four main rarities are Common, Uncommon, Rare, and Mythic Rare
This commander lives for the second main phase
Each Set Booster contains 12 Magiccards, 1 Art Card, and 1 token/ad card, Helper card, or card from The List (a special card from Magic's historyfound in 25% of packs), with a combination of 14 card(s) of rarity Rare or higher and 37 Uncommon, 37 Common, and 1 Land cards
Thats still not that great and probably not worth spending a card on, but you could certainly do a lot worse than Tangle
When my partner Wendy first started playing Commander, one of the first decks she wanted to build was The Ur-Dragon