With Energy Shaper keep Blizzard because 6 spells when shaped into 8 spells are good. You can keep Sivara with Wildfire in attrition matchups.
Put together a Casino Mage list that’s actually competitive! Some unusual play patterns to note that will help you play this deck to it’s fullest:
If you have Energy Shaper in hand and are planning on laying it down soon, discover spells by their cost instead of what they actually are. Best option is by mana curve, or the next best is 5/6 cost spells (which will upgrade to 7/8 cost spells) because these spells will usually work well with parrot.
When selecting spells off of discover, choosing spells that only target enemies or that generate minions are always desirable because your spell repeat cards, including Parrot Dawngrasp and Rommath, will recast the spells without targeting (so target spells risk hitting your own minions/hero). Thus, good repeatable spells include things like Blizzard, Flamestrike, Drakefire Amulet, and shenanigans like that from other classes. For the same reason, the best spells to get off of Vast Wisdom are usually secrets – especially spell-schooled ones because they will repeat for Dawngrasp.
Commander Sivara is versatile but must be used correctly. She can be used aggresively (wildfires, burn spells) or defensively (blizzards, alibis) so make sure you know the right context of the matchup and the right way to use her.