Here's the Wizard101central wiki page for her about her cheats...
- Casts a -50% version of Smoke Screen as an interrupt on the first round and every round you successfully cast a spell (a fizzle doesn't bring reprisal).
- She will stop this when a player has blades and she has traps (the clouds will part).
- For each round the clouds have parted, she will say "The cards align! Now's your chance!"
- Both her Smoke Screen and Smoke Mantle spells are -50% instead of the normal values.
So I went in with the following...
1 Fire Prism (for the Stellar Protector)
2 Fire Trap
2 Elemental Trap
2 Elemental Blade
4 Glacial Shield
1 Power Link (something extra to throw on the Stellar Protector, if necessary)
1 Heck Hound
1 Fire Trap (I had it, thought why not)
This is the case where Empowerment plays second fiddle to Infallible. You're probably going to be generating pips, since half the time you won't be casting because of fizzles. Also, it's probably not a good idea to do the 'dot' based spells (scald/link/power link/dragon fire/rain of fire) on Mithraya UNLESS you have an Elemental Shield on her. However, Heck Hound was a great finisher. You are likely going to be close to full pips on more than one occasion as the fizzles get going, and if you do manage to drop the smoke screens by keeping blades and shields up, before firing off any of your big guns, make sure to get more blades and traps on.
Unfortunately, I think I hit a bug, as though I had traps on, since I used up my one blade I had up for the Heck Hound, even when I finally got another blade on, she kept casting smoke screens on me. I thought, whatever, she's almost dead. Just kept casting Helephants and what all until one landed. Stellar Protector went down AFTER she was down.
I may try and streamline the deck with the above in mind...
2 Fire Blade
4 Elemental Trap
4 Elemental Blade
3 (or 4, if got right deck) Infallible
3 (or 4, if got right deck) Pixie
2 Heck Hound
4 Glacial Shield
In this case, you only have to land one of each of the Elemental Blades and Traps, and Infallible isn't much required once you have the blade and trap on, so discard those to get at what you need. Save the Heck Hounds for finishers, and use powered up Efreet to drive down Mithraya's health.
To be super fancy, you could take out all the damage spells and make Gargantuan versions of your damage cards, putting them into your sideboard. The majority of your main hand will be blades/traps/shields, allowing you to just keep attempting to put them on until enough has stuck, then pulling out your damage cards when you need them.