What Are Cells and How Are They Used?
Cells are special items which you can place on your equipment to gain extra abilities and damage bonuses. There are three tiers to the cells from +1 to +3 with the higher tiered cells being more powerful. These cells can then be placed in your weapons and armor for powerful boosts. The Middleman can take lower tiered cells and fuse them together into a higher tiered cell.
How to Get Cells?
The main way to get cells is from slayer cores, which themselves have several tiers from bronze to gold. You get slayer cores by completing quests, increasing your mastery levels and from the hunt pass.
Every time you get a slayer core you need to go to the core breaker to open it up. You can see that you have unopened cores from the gold symbol on top of the core breaker. When you break a core you will get a few random cells depending on the tier of the core.
You can also get cells as loot from killing behemoths, but against lower tiered behemoths these are generally few and of the weaker variety. And finally, you can buy up to three cells from the middleman every week for platinum.