No, you don't get these cards in a normal Chaos Legion pack. (I continue to open one of these every day.) This special, treat, Gladius Cases can only be obtained by successfully fighting other guilds in Brawls.
After the very well run Brawl of Jan. 24, 2022, I was able to afford three Gladius Cases. In one of them I found this legendary fighter. The other cards in it are nothing to scoff at either, but let's turn to the star in it: Fina Foxcom.
Fina Foxcom
Fina is half ghost, half elf. She is a melee fighter of the Fire Splinter. Even at level one, Fina has three attack points, a speed of four, and over seven points of health. Her most important trait is her opportunity, the ability to pounce unerringly on the enemy with the lowest Health. This sure eye, coupled with the bloodlust inherent in all Gradiators, makes her the Fire Splinter's most dangerous gladiator.
I hope to use Fina successfully in the next Brawl, which will take place in three days.
More details about its properties are shown in the graphic below.
Thanks for reading and have fun and success in the game wishes you your 
.
Acknowledgements
All Screenshots: https://splinterlands.com
Photomontage: own work based on screenshots from https://splinterlands.com
Translated with www.DeepL.com/Translator (free version)
Already published in this series
Part #1 Mycelic Slipspawn
Part #2 Molten Ash Golem
Part #3 Soul Strangler
Part #4 Scavo Hireling
Part #5 Angelic Mandarin
Part #6 General Sloan
Part #7 Xenith Monk
Part #8 GOLDEN Obsidian
Part #9 GOLDFOIL LAGENDARY Soul Fiend
Part #10 GOLDFOIL Scavo Chemist
Part #11 Obsidian (regular)
Part #12 Regal Peryton
Part #13 GOLDFOIL Hardy Stonefish
Part #14 Merdaali Guardian
Part #15 Mycelic Infantry
Part #16 Acid Shooter
Part #17 Tarsa
Part #18 GOLDFOIL Scavo Hireling
Part #19 Three new Airdrop Cards
Part #20 GOLDFOIL Blinding Reflector