Look into tracking garrison invasions from the previous expansion.

Would it be feasible to track garrison cache too? This one is a little trickier since it's got a variable cap (either 500 or 1000, depending if the player upgraded it). And not even sure if the server actually returns the cache current amount.

if i get the garrison tracking added, then yes - i'll add the cache too.

• Garrison Invasion Challenges -

Bronze Challenge = 37638
Silver Challenge = 37639
Gold Challenge = 37640
Platinum Challenge = 38482