Friday Mini CTF

Greetings to all habratchiteli. I love to poke my brains with different puzzles - these could be some kind of math problems, interesting puzzles related to programming, or some kind of ctf task.

For those who want to diversify Friday with puzzles, I want to offer my mini-ctf, in which there are only three puzzles.

XT_CTF_01
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XT_TASK_101

Link to task: xt_task_101.zip
Flag format: XTGFLAG {...}
SHA1 flag: 6980D76C3C5246A101820A77031CA0EBE84A4A0E

XT_TASK_102

Link to task: xt_task_102.zip
Flag format: XT {...}
SHA1 flag: 16448BF22750DE7E575A5A86E739FA9018ACFE52

XT_QUEST_103

Link to task: xt_quest_103.zip
Number of levels: 15 + bonus

Each file is a separate task (well, or in the case of 3 tasks - a quest), they are not related to each other. The purpose of the first two is to get a flag whose format is specified. As an additional check, I indicated flag hashes so that you can easily check whether you solved the puzzle correctly or not. The quest consists of 15.5 consecutive tasks, where a new one opens after solving the previous one, the answer to the current task is the password from the archive with the next one, so a separate hash is not required for verification.

There are no executable files in the tasks, no dependencies on any external services. Anything can be used - Google, online services, favorite programming languages.

I rate the complexity of the tasks as medium for tasks and easy for a quest. It would be great if commentators refrain from prompting in the comments (or at least hiding under a spoiler), so as not to spoil the decision process for those who will decide later.

A page on github , if it's easier for someone to save a bookmark there.