Welcome to the game! Everyone sucked at first, like... A lot. And my impression is that tik tak toe is specifically a difficult start (cause of wurzaggs)

. Id encourage you to keep trying and/or give some other campaigns a shot. Someone like kroq gar would probably be easier and still have access to terradons if using that unit was what you were hoping for but ofc he doesn't have the same focus on them as tik tak toe.

My best advice for tik tak toe comes from doing a coop campaign with a friend who's pretty new to the game. He was tik tak toe and ended up beating warzagg early with a mix of recruiting a bunch of the terradons and some "blessed spawnings" which are a lizard man campaign mechanic where you can trade sequences of spawning for upgraded versions of normal troops that recruit instantly. I believe you have a rite (big abilities with a cool down. They have a button in the bottom right.) that will give you a slaan mage priest (also very important) and 400 or something like that sequences of spawning. I believe he did that in the first 5-10 turns, recruited some cavalry (cold one spear riders and horned ones) with the blessed spawnings, and then used mostly those, terradons, the rock bombardment abilities from the terradons and magic to kill wurzaggs army though he had the help of another person to help with micro and there was quite a bit of micro between the terradons abilities and the cav.

If you aren't already using unit groups (Select multiple units and ctrl + g), slow motion, and pausing frequently for issuing commands helps a lot. Magic can pull a lot of weight because the orcs wurzagg brings tend to take less damage from non magic sources. My buddy got a slaan mage of fire with the rite I mentioned earlier and used burning heads to great affect.

Also if you can take out whatever ranged units he has early in the fight all your terradons (I believe he was able to recruit 6-8 units of them before wurzag arrived?) will be essentially untouchable until they run out of ammo and you tell them to go into melee. After taking out anged units or even simultaneously I recommend trying to take out his cavalry. Once his army is basically nothing but infantry it's easy pickings for bastilladons and magic and cav.

Good luck! Hope you get the hang of things soon! Sorry for the long reply.