SMITE

As Ix Chel, empower Great End to its maximum duration.

Great End is Ix Chel’s ultimate ability. When used, she fires an intense beam of light directly forwards. It will hit any ally and enemy, healing allies and damaging enemies (if you’ve played Overwatch, imagine Moira’s ultimate).

It has a base duration of 3 seconds, with healing/damage being done every 0.2 seconds, but if you hit both an ally and an enemy at the same time, the duration will be increased up to a maximum of 6 seconds.
It’s not particularly clear how long a single hit of healing and damage increases the duration by, although it appears to be 0.2 seconds per successful tick.
This can be done on the same ally/enemy, so if they were to line up and you consistently hit both of them at the same time, that would work.

Be careful though as it deals increasing damage to the enemy god, so they will quickly die if they aren’t super tanky. For a visual aid, when you use the ability, a white circle will appear around your ability that acts as a countdown. When you’re hitting a successful duration increase, you’ll see the timer jump up a tiny bit.

This is likely best attempted in Arena, although Assault would work well too. Laned modes like Conquest and Slash could work in the late game when everyone is grouped up, but it’s a bit more luck based.

You don’t need to build any particular items, although some CDR might help to use your ultimate more often.