You can just do coop to safely farm boss fights without the risk of dropping the runes. Or…
You can get 150+ in <1hr if you grab a great bow and make a beeline for the Varre quest. There’s a bird you can repeatedly bait into suiciding without moving more than 10 steps from the grace. Or if you turn 180⁰ there’s a whole swarm of albinaurics that give you even more runes/min if you have good AoE damage. There are plenty of extremely easy options.
You can just do coop to safely farm boss fights without the risk of dropping the runes. Or…
You can get 150+ in <1hr if you grab a great bow and make a beeline for the Varre quest. There’s a bird you can repeatedly bait into suiciding without moving more than 10 steps from the grace. Or if you turn 180⁰ there’s a whole swarm of albinaurics that give you even more runes/min if you have good AoE damage. There are plenty of extremely easy options.