What does farming event circles give without donating?

Fine. Let's do it again. Let's see what we can get.

70 lap:
Two heroes
Robot
Red collectible

Either
Hero
Two robots
Ax to the gun

And more garbage.

150 lap:
2 heroes
Robot
Red collectible
For 100-robot/red collectible
For 150-hero/statue/Ice Crystal Kiss/ax

For 80k diamonds.
Along the way, he will sprinkle fragments of robots. Under 300 pcs. You can upgrade some robot to red.
Antimatter cubes 25 pcs. Approximately.

Each hero provides a 10% attack bonus and a neurolink.

At 200 there is the scepter of Dionysus. Rare red collectible that is not in the chest to choose from./crown/eye/robot

On lap 240 (105k+ diamonds)
Hurricane/Gale Shinobi/ax/ 2 statues/robot skin.

And now the main thing.
It costs absolutely nothing.
You can accumulate 40k from event to event and boost BM from heroes.

If you don't want to, don't participate.
The whales don't want to participate because they have all the heroes. There is little benefit for them.
Compare with a cybermaze or laboratory. How many prizes are there?