Runes and hero growth
Spirit Altar Greater/Epic Runes
Collect the Greater and Epic Runes needed for an elemental hero's awakening using a difficulty that reliably supplies them.
Battle > Spirit Altar > the open altar for the target hero's element.
Repeat while the matching altar is open and more runes are required. Element availability rotates; the farm is not continuously open for every element.
Stop when the planned awakening's rune count is met; spend Energy on another open altar or progression goal.
Open a guide to find other locations and see what the item is used for.
Collect the Greater and Epic Runes needed for an elemental hero's awakening using a difficulty that reliably supplies them.