Open up the grimswarm arena, have it available to the public for simucoins. Spawns similar level grimswarm in waves, starting with 1, then 2, then 3, then random 2-5 with higher chance of 1-2 grizzled. Reward one chest per wave, higher wave counts generate higher tier boxes in loot. Also make loot susceptable to hunting pressure depending on level. Reward a free token to reenter if you make it past 15 waves, and grant something neat for 25 waves.
W3 4R3 4N0NYM0U5.
W3 4R3 L3610N.
W3 D0 N07 F0R61V3.
W3 D0 N07 F0R637.