Hello everybody.
I'm pretty sure the thing that I'll be showing you now is a bug (Although I can still hope it isn't), but it is a funny one and can be very interesting for map makers.
You can make players unable to jump.

It works very simple:
As most of you should know, you can type the command /effect <player> <effect> <seconds> <amplifier>, to give a certain person a certain effect with a defined duration and strength.
If you replace <effect> with 8, it will give you the Jump boost effect. The maximum amplifier is 255, however everything will be buggy above 127.
So if you type the following:
/effect <player> 8 10 127
You will get a very strong jump boost for 10 seconds. (One jump will get you ~400 blocks high)
However, if you replace the <amplifier> with anything from 128 to 251, you will NOT be able to jump!
For example:
/effect <player> 8 10 128
I think this will give map makers a lot of possibilites so I thought I'd share this little bug/feature with you.

For those of you who are wondering what happens if you use an amplifier from 252 to 255:
Nothing (You will jump as if you had no effect) except for 252.
If you use 252 as an amplifier, you will jump exactly 0,12 blocks high, which is actually close to nothing and doesn't change anything, but I thought it's still worth mentioning.

That's already it. If this little Tutorial helped you, feel free to diamond & favorite or subscribe to see more.
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