At the moment, there are 13 epic units in the game, toilet tower defense. Few epics are limited, few are still obtainable. The unobtainable epics are the units that was obtainbale during the respective event. These units can be obtained by Summon Crates, Event Crates. Some epic even have good stats, with good damage + AOE.
According to me, the epic units that we get from summon is not better than event epic units. So i would tell it would be better if you choose to use epic units that are from event, and that are currently obtainable. Because you’ll get them for cheap and later you can flip it when its unobtainable.
When Are The EPICS most demanded?
During the release of update. If we get any new crate, and if it contains epics then you can sell it as the new units always have great demand. But be alert because these new units drop very fast. So try flipping these units ASAP!