Notes & Combos
I had a thought that denying your opponent of the graveyeard seems pretty good in this current meta (especially with Branded and Sky Strikers everywhere). You'll still run into the usual bricking issues Kashtira has always had, but Subspace Battle has been a pretty big game changer for me after trying it for a bit. Being able to have easy access to Kaijus and Lava Golem is a nice thing to have. Liberator Eto is to beat out the opponent's big ATK monsters when using Subspace, but he's also been fairly useful just as a big body you can summon from your hand or GY. You can replace him with another big Kaiju or any other big monster you find useful, though if you can't decide then just go with a second Ascended of Thunder.
Feel free to mess around with whatever Super Poly targets you prefer and you can also mess around with the rest of extra deck if you want to aside from the Kashtira cards.