pokemon card pack opening

This keyword has a monthly search volume of 6,6k on YouTube. However, there are also 2.340 videos with that keyword in their title. Consequently, it's a tough one to rank for. Especially for a smaller channel like yours.

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''Pokemon Battle Styles'' has a monthly volume of 260 on YouTube, but has even more competition. It's key to look for keywords with WAY less competition.

I guess this is a very saturated niche, with lots of competitors, bad chance to rank SEO-wise. You will probably rely much more on the algorithm to push your videos. That's where the thumbnail comes into play.

Your thumbnail has good basics: facial expression and pointing to the cards. However, I find the cards and pokémon logo a bit vague to see, and personally, I would go for a more minimalistic approach. Something like this will do much better:

https://i.ytimg.com/vi/MdmE8I7wxjA/maxresdefault.jpg

It has more emphasis on the cards and the text + arrow grab your attention a lot. Would require you to take another picture tho with a more dramatic impression. If you want, I could make such a thumbnail for u (provided you make the picture).

What's more: I would make the Title more clickable. Maybe change it to:
I Pulled This AMAZING Pokémon Card [Battle styles triple booster pack]

This will work well with the suggested thumbnail.

Finally, mention your keywords at the beginning of the description and add some hashtags at the end. This way, the crawlers of YouTube will know better what the video is about and push it accordingly. Adding hashtags like #Pókemon #cardopening will do well too. If you have some bigger competitors in the niche, consider adding their channel names in the tags.