Цвета крови сухая земля,
И янтарные очи дракона
Отражает кусок хрусталя -
Я сторожу этот клад...
New here? I'm Roha — want a quick tour?
Yes, in theory...
It's better to move on to practice ;)
Without acceleration, it's unlikely to work, and the chances are slim. But if:
1) Place Hydras closer to the gates.
2) As soon as the Hydras' turn comes, cast acceleration on them (not earlier, of course, otherwise they will slow down).
3) Skip the Hydras' turn (the speed of Chaos Hydras is 7 by default, and skeletons have 5, even if the latter skip a turn, the former will move after them => skeletons will not be able to attack in the same round).
4) Bring the accelerated Hydras out from behind the gates and attack the skeletons.
5) Next round. On the turn of the Serpent Riders (ideally the first, otherwise after the Phantom Dragons), teleport the Hydras back behind the wall.
That's how I see it, but the Hydras may suffer losses from the enemy undead, the skeletons may block them, and there are many other drawbacks. But you asked for a fantasy, so here it is.
...there were 2 more questions about heroes... maybe someone will answer. About Tazi and Crag Hag, etc.
Let me explain it step by step. Whoever moves faster attacks first, and the more damage they deal in one hit, the less damage they receive in return. Whoever moves slower gets hit first, and the better their defense, the more damage they can inflict. Attack only affects melee combat, while armor, although with a lower percentage, affects all types of physical damage. In general, for your overall knowledge, read the Physics Guide – there is a topic about this, find it.
In general, it's better to recruit the hero who arrives earlier.

