This rule gives more power to the stun ability since all attacks to stunned monsters will do double damage. Stun is on of those Randomize luck abilities that you can use when up against better opponents as it gives you a better fighting chance. Since 50% of the time the stun will hit you have an equal amount of chance to get unlucky. For this reason, I rarely focus on it even when being given the Heavy Hitters Game rule. Basically, I rather not count on luck and go by my own power as it always kind of feels you stun misses a lot more compared to hitting. I would say for Speed and misses this is the opposite as you can get well over s 50% chance for the opponent to miss.
I did however play a monster with stun just for the sake of the challenge...
So I played a variation of the Water deck Possibilus Deck with a small adjustment adding in a monster with Stun. With 50 Mana to spend, I played the usual double tank combo of The Kraken & Arkemis The Bear. Since only even mana monsters were allowed, I didn't manage to add some Tank Heal. I played the Medusa in 3rd spot hoping to get a stun on either the 1st hit and/or the 2nd hit which are the most crucial. This however didn't come until the 3rd hit so it did more harm than good. The Deeplurker also always is included in this deck and the downside with the rule it that the Heavy Hitters never will activate since it generally doesn't target the first monster. In the back, I played The Ruler Of The Seas which pretty much is an auto-include in all wild Water decks and the Naga Windmaster to both diversify the attack types and to possibly decrease the attack of the opponent a bit
While I had 63% chance according to Splintools, this was probably highly dependent on a stun from the 1st attack which didn't come.
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