They seam to appear randomly with a low probability that is upgradable. They never seem to appear when I've first started playing though so I doubt it's truly random.
XandrakeG it isn't grindy at all... it's focused on offline play while your character is sitting at a low level and you are logging on to upgrade, then logging off for cash, then when you've reached what you consider to be a ridiculously high level you shoot up the levels, get more time cubes and then restart to rinse and repeat.
Recently restarted after running up the ranks for a ton of cubes, on level 79, offline for 2 min 136E36, upgrade then back offline for a couple min, then get 1.74E39... you get this progression, it's freaking insane, in no time I'll be way above where I was before. all for not playing the game, just logging on to upgrade and then logging off...
People downvoting my post are idiots. You should not be able to get cash in the range of 98E51 easily while offline on level 84. It's not right, and it's stupid. It makes the game about offline play, not actual live play.
This is very odd.... I've found something that is kind of a cheat/exploit... but is clearly a badly planned way the offline earnings work. The best way to make money in the game is to stop progression at a very early level and then upgrade your team massively. You can make insane amounts of cash so that you can upgrade your team ridiculously before you ever really start the game. It seems to not limit the amount of times you can clear the screen per second on offline earnings mode. So when the game is open you make nothing in cash, but when you're offline you can earn crazy amounts of cash in minutes while offline.
For those of you whining about the loading resources screen, you're idiots. You can buy upgrades during that loading process and they increase the bonus you are getting. It's like you get to play all those hours you were offline at supper fast speed. It's one of the best features of this game.
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 "Idle Business"){kind=icon}
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 "Time Clickers"){kind=icon}
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We save on close, every 5 minutes and when you take an action like buying a Crusader level or changing fields.