Shirimani aka the Frost Queen is a Force affinity legendary champion from the High Elves faction. She has an AOE freeze ability which is one of the strongest enemy control abilities in the game although be aware freeze does make your champions hit for 20% less damage. Shirimani works fantastically as a go 2nd champion behind your speed booster to completely lock out all of your enemies in arena. This allows your damage dealers more time to get their big nukes off on your enemy for an easy win.
Shirimani is also a great champion to help you beat Spider 19 by freezing all of the spiderlings and utilising the heal on her A2 ability. She is solid anywhere in the game and usually best to gear her in speed and accuracy stats although she also hits really hard so some crit rate and crit damage can turn a good build into a monster build.