Here is the link to the blog post describing super ascension:
https://www.warzone.com/blog/index.php/2021/11/update-5-16-super-ascend/After spending 100K AP in Phase 4, you can Super Ascend. Super ascending is almost like starting over completely. You can pick 2 artifacts to keep (that number can be upgraded), and you keep rewards from previous super ascensions, powers*, and the supercamp (if you bought it). Everything else is reset, including all AP and advancements.
You then have the option to choose one of the following rewards (which stack):
• +25% AP from levels
• +1 additional artifact when super ascending**
• +20% faster artifact digging***
• +100 starting AP after super ascending
* Powers do not regenerate between super ascensions, so if you already collect a power twice, it will be gone forever.
** If chosen on the first ascension, you will be able to keep 3 artifacts during that ascension. That number goes up to 4 if chosen a second time, then 5, and so on.
*** This boost stacks the same way other dig speed boosts stack, each boost will be multiplied. For example, dig time will take 80% of the original time after this is chosen once, and 80% x 80%, or 64%, after chosen twice.