Being online only has two effects.
1. It makes it exceptionally difficult to make a trainer that works only in single player mode. Multiplayer cheating is not something Cheat Happens supports.
2. It makes changing stats difficult if they're stored online. This makes options very limited.
Diablo 3 was a very good example of always having an online connection destroying an opportunity to make a good trainer.
I've read on their forum they plan an ingame shop, might be the reason why there is no offline mode. However as long as there is no offline single player, there won't be a trainer on CH for this game.
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