Replay stage

Every time you exit and replay a stage (campaign or dungeon or abyss), a new seed is generated that will influence events. This will not happen if you just hit restart.

For example, let's say you are playing a legend campaign stage and your aurai keeps getting killed at the beginning right before she is about to ult. If you exit and replay, the sequence of events will change (for better or for worse), and aurai may survive the new seed.
Or in dungeon when you seem to be having terrible luck with pulan freezes not working no matter how many times you restart. If you exit and replay, the miss chance will change.
So, if you are having a great attempt but lose by your own error near the end, make sure you restart instead of letting the battle end. You will keep the same seed, so you can just correct the error that you made (assuming you can sufficiently recreate the progress up to that point).

2 Small tricks I have discover that didnt seem so obvious

1- Magic squares give only 300-500 coins every 2 week, that is only 12-18SS per month. But I have seen I get almost 3k coins every 2 week (60SS per month), and the reason its that ANY point you get playing is directly converted in shop coins, so stop ignoring your alliance leader and start playing magiapoly.

2- The talents group have an "activate" button, it make you think that you can activate and deativate them, so in fact you can only have 1 activated at the same time, but the reality its that you can have ALL talent group actives in a hero at the same time, that button is useless and only cause confusion, and in fact talent are more useful that they seem when you discover this.

A tip on saving meds on world monsters

So some of you might know this, but if you use up your attacks at the end of the day on solo lvl 5 monsters that give a little gold and a prize do not heal your team(s). Heal your team(s) when you are finished with all the attacks. You will save about 1k or more in meds if you wait to heal them vs. healing then every time they return.

Thanks for advice Flatulent_Dragon from Reddit MRH