A summoner becomes great once you have enigma, allowing you to teleport all summons and merc on top of a monster to instantly kill it, then casting corpse explosion can eventually deal enough dmg to kill the whole screen (when paired with Amp and Infinity).
It’s gonna take a while until you reach that point.
Prior to having the full end-game build, a summoner is still a very noob-friendly build that can slowly walk through the game even if you have no gear at all.
Max both skeleton and skeleton mastery.
This is your main dmg, the skeleton mage are useless, no need to summon them.
Amplify damage curse will greatly boost your skeleton warrior and merc dmg. Cast it on everything you see.
Once you have maxed both skeleton and skel mastery, with 1-5 pts in amp, you can start maxing corpse explosion.
This will become your main dmg, but it cost a lot of mana. Each lvl augment the area of effect, not the dmg, but it’s well worth it.
The dmg is based on a % of the monsters hp, but it doesn’t scale with the bonus hp they get per player… this is why this build is ideal if you play alone, or at a low player count.
If you lvl up with a friend, the best summoner allies are :
Paladin
His aura boost your army, your curses boost him
Sorc
She can enchant all your summons and both merc, and if she use static field then your corpse explosion can 1-hit kill everything that was lowered by her already.
That’s a very brief overview… but if you have question you can pm me
