This is how I got my 6 slots skill rune plus other tips - Undecember

UNDECEMBER on Steam

UNDECEMBER

Undecember: The Best Mage Build (Weapons & Runes)

How abilities, runes, essences, and storage work in UNDECEMBER: Everything you need to know - Dot Esports

Feedback and Suggestions - If they don't upgrade to Poe 2, the

Undecember SEASON 3 Updates - New Runes/Uniques : r/undecember_global

Rune Basic Guide for UNDECEMBER! Covering some of the upfront basics!

Undecember act 11 new skill and link runes : r/undecember_global

UNDECEMBER 언디셈버 - ALL Skill Runes Showcase (Active Skills) +stats +tags

Skill Rune System Guide & Tips! Hopefully it helps new players! : r/undecember_global