I don't have numbers to back me up on this one yet, but it is the general opinion of the forums that digging for fields with more than 1 imp at a time is a waste.
We may never know why, but regardless of how many imps are in a dig team, the team can only excavate a maximum of 7 fields per 10 minute session. More imps does not seem to increase this.
Whether you have 1 imp or 12 imps, the chance of excavating only 1 field appears to be the same.
Don't excavate for fields until you are almost ready to use them. The more fields you have in your dungeon (whether they are used or not), the harder it is to defend.
- Only excavate fields when you are ready to use them (this helps your defense a little)
- excavate with a 1-imp team for only 10 minutes at a time
By far, the most effective way to gain points in DignFight is by excavating for gold with imps.
Attacking with imps is bad!! Although imps can carry much more than any other creature, if you lose 1 imp, that can set you back more than 3000 gold.
Even if you recruited an attack team of other units (devilers, wizards, etc), you have to make educated guesses to find the right opponent to attack and there is ALWAYS the risk of taking damage (which is very expensive to heal).
The best use of your time and money is to recruit a team of 12 imps for digging.
- always dig for only 10 minutes at a time. digging for 20 or 30 minutes at a time does not double or triple your "harvest"
- you will excavate less gold per 2 hours if you excavate with multiple teams of fewer imps (3 teams of 4 will bring back much less gold than 1 team of 12)
- upgrade as many imps as you can as fast as you can. the sooner they are upgraded, the sooner their carrying capacity is upgraded.