Welcome to the beginner's rune guide for Summoners War: Sky Arena! We will be briefing There are currently 6 slots available in the game. When you equip a. Violent runes can replace majority of units 4 slot rune set and 2 slot as it will work on % of all units. Despair and Revenge runes may also. chart is taken from SW wiki (http:// summoners - war slotsmachineonlinefree.review Runes), .. Invest in speed rune slot 2 and many speed sub-stat. Is slot (2) & (6) really that rare?.