I'm just playing through the tutorial, and having a surprisingly difficult time keeping my ranged units alive. The AI clearly targets them, and I only have two stacks of melee units so I can't form an effective wall around my squishy units.
What should I be doing differently?
Here a few ideas
Use your healing skills. Healing and Regeneration are obvious candidates, but I'm a big fan of the Reinforcements skill. You can only use it once per combat, but it allows you to "overheal" your unit by giving them extra units. Not only do losses get taken out of these units first, but the extra units also increase the damage you deal.
Use the tactics skill to start the battle with your ranged units in a protected spot.
Use Guardian Angel. Your faction ability doesn't cost you any mana, and it doesn't even take your hero's turn, but it doesn't carry over from one battle to another, so you should be using it whenever you can.
Use your Sentinels. Each Sentinel unit standing next to an attacked unit will absorb and split some of the damage with it. If you upgrade them, they even get to retaliate when the unit next to them is attacked.
Use your Sisters' healing ability. Twice per battle they can heal, so make use of it effectively. Don't use it early if you haven't sustained the full amount of damage that you can heal. Beware though that the AI will generally target Sisters before ranged units. =)
When they are being attacked by a melee unit, make sure they don't get hit by retaliations. The ranged units are fast, so they will act early in a turn. If there is something next to them when there turn comes up, have them wait. When they come up again, you can either move into position to shoot at the beginning of the next turn, or melee attack something that no longer can retaliate, or possibly even shoot if you've killed the unit next to them in the mean time,.
I have been having a similar problem. I have only come up with a few ideas, none of which are perfect.
One is to use the hero to cast defensive spells on the ranged units. Another good idea is to have your ranged unit hide behind a rock on the map to provide cover from the opponent's ranged units. Lastly, you can split your melee units. So instead of a stack of 50, make two stacks of 25. With more smaller stacks, you can more easily make a wall.
I've had little trouble so far myself, although I'm still on the first mission, though fairly deep, and I haven't even needed to use defensive spells on them. Bwarner's last tip about ranged units being fast is very good, proper use of the wait command is very effective.
Splitting your Sentinels/Praetorians is very helpful as well, especially once you have 80 or more. You can easily keep a pair of relatively small stacks near your range units to split damage, and get those free attacks in if the ranged do still get hit. I've been using two stacks of Praetorians pretty much the whole time, being aggressive with both, and so far have had pretty great success in meeting enemies in the middle and cutting them off.
Flawless Assault is really good as well, in a proactive sense. Those archers hurt when they hit for full damage back-to-back turns. Rush is also a good proactive "defensive" measure, as you can rapidly get your Praetorians engaged with the enemy units, allowing your range units time to dump damage without fear of being prioritized.
