MArcomage

I think remove the tower, or just remove the doubling effect of N for tower.

if N=16 then you do 20+4*16=84 attack and you also get 32 tower out of the deal for only 30 recruits.

N usually will be from 8 to 11. It's from 52 to 64 damage and from 16 to 22 tower. Compare it with Forest dragon. He can do up to 160 damage but usually does 70-80 for 36 recruits.
Maybe I should reduce damage multiplier? Say, make it 7N/2 or 3N?

2N might be better. The thing is, that you can achieve victory in 2 ways with this card

1) with Tower built
2) with Tower destruction

Granted, 2 is more achievable than 1, but it's still there. And in Nature/Beast decks you should view N as 9 averagely, which is still a lot of attack and a lot of tower gain for just 30 recruits.

Don't forget that for Forest Dragon to do 160 damage, the enemy needs to have Nature cards as well. That's not the case usually, so consider that forest dragon is doing 80 attack for 36 recruits, and gives you the ability to bring another rare (as this card does as well ofcourse).

That's too many effects for just 30 recruits.