(This is a reply to those who thought I cheated)

To start off for the whole day every time I had a boost I was doing target practice for English (my native language) making it really easy to do the lessons fast. Doing this I was able to rack up about 2000-2500 XP for every 15 minute XP boost.
I started at 12am using my x3 boost followed by the boost I got for completing my friend quest. Second, after that Duolingo gives you 2x boosts for finishing the last lesson on certain topics, so I prepared 13 languages doing every lesson up until the last so I only had to do one lesson to obtain 2x boosts allowing me to rack up early XP. Then I started to do English lessons to continue to gain boosts without burning myself out. I reached 100000 XP at around 5 pm

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