Is it bad to play minecraft or any other games in my MacBook Pro? Does it makes my laptop slower?

It's not bad. You can use your computer while it's being charged without any problem, and it won't decrease your battery life. For more information about Macs and batteries, see > http://www.apple.com/batteries/notebooks.html

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It's not bad and it won't make your computer slow. Games and heavy apps make your computer work harder, so you have to control the temperature of the computer.

To do it, fans should turn on automatically when temperature increases, but anyway, you have to take a look at the temperature manually. This is important, because high temperatures may reduce the MacBook Pro's life. Apart from that, nothing to worry about

When you play video-intensive games, your MacBook works really hard. This makes it use up the battery quickly and it gets warm. When it gets warm the fans run faster because their speed is based on measured temperatures inside the Mac. Faster spinning fans use the battery more quickly as well.

But all of this is exactly what your MacBook was decided to be capable of doing. If it had a flaw that caused it to malfunction and get too hot, it would shut down long before the heat does any permanent damage.

You can lessen the load slightly by adjusting the graphics parameters inside Minecraft to reduce the render distance, fog rendering, display quality, and "automatic" graphics features.

You can also sit next to an outlet and plug it in.

You are welcome

When I play, my macbook Pro gets really hot and I lose battery really quick. Should I just not play just in case?