You have the following available for all the stats (or you should):
Regeneration is comming from the following :
- from tokens
- from player's stats
- from creature's stats
There is no VE used from player, there should not be any VE bonus (after battle ) from tokens.
For a creature to regenerate to 100% it will have to have 100 Regeneration.
How does a creature gets 100 regeneration ?
Well ... it can get through those listed above (I hope I haven't missed any).
But there is just one trick : players regeneration is based on the influence used while starting the battle or defending in it. lets say 60%.
Well, after the the influence has been chosen, it counts the number of creatures and splits the remaining stats between them equally regardless of the bonuses between them.
So, considering that a basic/normal creature would have 0 Regeneration of it own, for it to have fully regenerated, while having a battle with 60% influence ... the player should have ....
1/(nb creatures in battle) * (influence / 100) * (Regeneration of player) >=100
1/6 * 60/100 * x = 100 ===> x = 1000 ===> the players should have at least 1000 regeneration for its creatures to regenerate in that battle.
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Have fun.