Nigon is the second underground race.

Then, better to focus on alternative upgrades: a troll-cannibal that restores health by consuming enemy units. Don't confuse it with vampires. They regenerate with each attack on creatures of flesh and blood, while trolls gain health when a creature from the enemy stack dies. And a siege troll – heavily armored and covered in spikes, with a huge spiked club. Bleeding and bloodlust would be suitable as special abilities. But I'm sure you have your own ideas on this, so I humbly ask you not to take my words as criticism of the project. Moreover, the ability of troll-cannibals is not very original and not entirely plausible. Think about it: how can you choose the right moment to take a bite in the heat of battle?