You can’t just jump straight into being British, silly, it's like baking a cake, you need ingredients! First you need to get a certain achievement before you can become the best bloke you can.
That achievements is:

'Can You Trust Them?-unlocks full stabbing potential!
(Optional for casual British "person", Required for TRUE bloke status)

This achievement can be done once you unlock the illegal den (got once you unlock 25 achievements) and by hiring 2 allies and completing a run. Simply hire allies before finishing an easy skeptic run to get this achievement and get on with becoming British!

-Aiko Takahashi, the British "person"

The first first step to Becoming British is genetic. This is achieved by being the British "person", Aiko! The faster combat action speed and higher dex (got from being British and not being the swim team captain, common misconception) is perfect for stabbing things. Just to praise the detail, she starts with a -knw just like a real British bloke!!! :D

To achieve the ultimate British bloke you must have the doggo shop and occult shop available.
This way you can access the ~~~Bloke Essentials ™~~~

(knife and knife accessories)

Step 1
Immediately go to the dog shop and buy a steak knife (a classic for Blokes) and a Tainted Violin to stab better and play the national anthem.

Step 2
Whenever you level up, level up dex inorder to improve your stabbing power (which is more important than stamina or reason to a true British Bloke)

Step 3
Profit & Stab

To misquote our lord and savior: Gabe Newell
"Welcome to England, after 2 hours in development, hopefully it'll be worth the wait. Thanks and have fun"~ Gabe Newell, Source: Trust, my non-existent uncle works at valve.

Also I’m not British, nor have I ever met a British "person" or been to the U.K.
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