'Strongest'. Extremely common in gaming and sports slang.

What a Japanese person actually thinks
Casual and a bit internet-flavoured. It's the register of a tier list or a YouTube thumbnail rather than anything considered.

Meaning

Literally: most + strong
Actually: The strongest. Everyday superlative — 最強のラーメン ('the strongest ramen') is a normal thing to say.

Scores

Naturalness●●●●●

Very common word.

Coolness●●●●●

It's superlative slang. On skin it reads as enthusiasm rather than conviction — and it inherits 強's appliance-dial problem in half of the compound.

Watch out

Nothing embarrassing lurking in here.

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剛 gō
unyielding hardness

Strength as character rather than as a ranking. One dense character.

On skin

最強

Orientation: either

Bold brush.