In Splinterlands, sometimes being a creep pays off!
You need a Creeping Ooze if you're grinding away for a spot on a leaderboard or if you just want a better win ratio, which means more DEC through the season. It is really important. Bronze rank monsters' speed (energy) are almost never higher than 3. Very few hold a 4 speed value, like Water Elemental. Shield tanks are even stronger than in higher ranks, because even if they're slowpokes, their attacks are a lot less likely to miss.
This escalates into Silver if you are playing rank, because as we get further into a ranked season, it is that much easier to climb. Before you realize it, you're having an easy time facing level 3 monsters or lower again. Across the board, every monster has low speed. It's not like you're going to see many people using Feral Spirit, because despite having naturally high energy, it is an expensive card for its common rarity. And that's why Creeping Ooze is so important!
It doesn't matter what tank you're going to use - Living Lava, Spineback Turtle, Sea Monster, Shieldbearer, Haunted Spirit, Flesh Golem, Chain Golem - they are certainly going to hit their targets if you have just one monster with the Slow ability. It might surprise you, but thanks to this, Sand Worm, Cyclops and other 1 speed/energy monsters are very strong at these ranks. The chance to miss attacks is only 10% for each 1 in speed/energy difference.
Just in case your DEC gain is worth it, a Gold-Foil Creeping Ooze is relatively cheap. Its burn value at level 1 is 750 DEC, but you can pick one up at the market for as low as 920 DEC right now. +10% DEC in every battle? That yells profit!