I would like to start off by saying sejuani is AP! (ability power) I have seen countless guides of people making her use AD (attack damage) by doing this you are taking away the best thing sejuani has, and that is her unmatched ability to nuke and cause great amounts of CC (crowd control), taking away her ability to do that in my mind is hurting your team more than helping your team. Sejuani fill several different roles such as start team fights/ganks, and tank for the duration of a team fight or gank, she can be a jungle on a team or even *if you know what your doing* solo the top lane, when sejuani dose enter a team fight she can nuke everyone down to half health *or more* and stun them for up to two seconds, so imagen the affect of knock the whole team down to half health and stunning them for long enough for your team and your self severally to wound or completely wipe out the whole team *or at the very least leave them so slowed they wont be able to get away* without any one taking any damage, therefore sejuani's skill chain is a true shock and awe.