As an avid Kroos Alter enjoyer who raised her as one of my first 5 stars, and seeing her featured more and more in sniperknights and IS3 clears, I wanted to make my case on why she's a very very strong operator worth raising - you'll have free pot 6 as well from the current event!

Comparison is between Level 80 S2M3 Mod 3 Pot 6 Kroos Alter and Level 90 S3M3 Mod 3 Pot 1 Exusiai. (Keep in mind that M3 mod 3 level 90 is probably double the investment on a 6 star than on a 5 star)

Purple is Exu, Blue is Kroos Alter

https://preview.redd.it/uaace6taicib1.png?width=1696&format=png&auto=webp&s=eef2c8b2c6bafec99b47dd0106132f5bc968cf74

https://preview.redd.it/00k9r8taicib1.png?width=1668&format=png&auto=webp&s=3c642231e9b4d3ff00df23a12b7cd6dff33d4297

https://preview.redd.it/av5ezdtaicib1.png?width=1686&format=png&auto=webp&s=8ce9bebe792a1851cc588675951002dd675257a0

It blows my mind that Kroos has very similar average dps to Exu, about 10-15% less. Of course, Exu's skill dps is significantly higher (but having half the duration of and lower total skill damage than Kroos) making her by far the better choice for similarly short duration atk buff skills like Warfarin.

But in IS2/IS3/IS4, skill dps matters significantly less and depends more on the timing on enemy waves. Speaking of which... we're comparing a manual activation skill with an automatic one!! Managing Exu's skill to match with enemy spawns is difficult and will almost always leads to some dps loss. Comparing with Exu S2, which has often been her preferred skill for blind clears (story and IS), Kroos outshines Exu (sorry don't wanna overload with images but you can compare them on viktorlab.cn).

If you don't have exu or don't have her built, please consider investing in Kroos Alter! She has comparable overall dps, higher total skill damage, more control, at a fraction of the investment cost. The only time she really feels any worse than exu is when enemy waves demand a 15 second burst and you want to set up a buff army with warf elysium etc who have skill durations that match Exu's.

Of course, comparing DPS doesn't consider exu's ally buff talent. But let's be real, that's going on myrtle. And Kroos has the utility in her microstuns (which are more consistent at attack cancelling enemies than you think with a significant attack interval reduction and 4 shots per attack). She is also imo one of the best picks in high ascension IS3 runs as operators with stuns go way up in value, and non-elite mobs actually don't have their def go up that high.

When Kroos Alter first released, you couldn't bring alter operators and guides recommended against building her as it locked you out of the very investment-worthy regular Kroos. But even back then, I think a 5 star with comparable performance to a powerful 6 star was more than enough reason to raise her. Kroos isn't going to powercreep exu (obviously), but she is definitely one of the best welfare operators we've gotten!

tl;dr Raise your Kroos and Kroos Alter! Kokodayo!