If the target creature is already tapped as it resolves, you will still put a stun counter on it
Dinosaur, Sea Serpent, or Thunder: Once per turn, if you activate a Spell Card (except during the Damage Step): You can inflict 1000 damage to your opponent
The biggest issue with this card is its considerably circumstantial, so while its pretty good, it wont always be the most useful card to have in hand
Its packaging is quite similar to the regular promo card packs that are given in certain situations but with transparent plastic
However, if you're not a collector or a Seel superfan, there's little reason to want this card
The ability to exchange excess Slime monsters for a draw could be useful as well, but should require the controller to have an Egyptian God on the board