Next tower will certainly feature a Linirean Barrack

It could be also a Dark Army Artillery, but we just got a dark army tower, so next wil be Linirean.

Altough many towers are very flexible, it seems that they are as follows:

Dark Army Ranged = Twilight Longbows / Ballista Outpost
Dark Army Mage = Eldritch Chanelers / Bog Hermit (magical) / Necromancer
Dark Army Artillery= Tricannon / XXX
Dark Army Barracks = Demon Pit/ Grim Wraiths/ Rocket Gunners

Linirean Ranged = Royal Archers / Dune Sentinels
Linirean Mage = Arcane Wizard / Elven Stargazer / Arborean Emissary
Linirean Artillery = Battle Brewmasters / Dwarven Flamespitter
Linirean Barracks = Paladin Covenant / XXXXX