Onagers make me to slow. I am fast-man, ZIIINNNGGGG and I'm gone!

I've always had luck with sap points, otherwise my army is all cavalry with a spy ranging ahead. I dont think I've ever used onagers

Hi,

I find it depends on the situation.
If the defensive ring is a wooden pallisade using a scorpion or onager makes sense. You can attack straight away, take out the wall at multiple points and attack.
This is especially useful if there are several armies nearby on the strategic map.
When assaulting stone walls, it depends on the ennemy forces defending the city. If there are only a handful of units within the city i find it annoying to have to wait a turn or 2 to build the relevant equipment to attack when you could just storm the gates. If its a large defending force, a bit of variety to the assault can help alot!.
multiple towers attacking the wall, a wall being sapped and an onager taking out towers/archers.

Ranged Siege Weapons can be used against armies. They are particularly useful for killing large, densely-packed groups of heavy infantry or generals. Also, they are better for attacking settlements with Wooden Palisades or Wooden Walls than on-site siege weapons, as they can attack immediately, not waiting for the siege and thus gaining the attacker the advantage of one extra turn of income from that settlement. They do slow down the army though.

On-site Siege Weapons are the best thing to use against Stone Walls and up, since Ranged Siege Weapons can't do enough damage to be very useful here. Personally, I like Ladders and Siege Towers, but I use Rams when I don't have any other way of opening Wooden Walls.

Another good trick is to use Elephants. They can knock down Wooden Walls and Reinforced Gates (although this means they can theoretically attack Stone Walls, the boiling oil will run them amok in no time). They do the same job as the Onagers, but without the problem of reduced movement points.

BI is correct; like everything else in this game, you must tailor your responses to the threats.

If the city's perimeter is wooden then a ballista and some rams will do the trick. Just put the ballista on the towers, then on the gate. Put the rams (2 or 3) at wide intervals on the wall. Wait until all points are breached and your troops are ready before assaulting.

If the city has a stone wall I find the following works well: Get some onagers (2-6) and rock the crap out of the barbican, towers, and gate. Build a few sapper points (3-5) and put your light infantry on them post haste. If you think things'll get dicey, send cavalry or heavy infantry for support. When the onagers have blasted the barbican, towers, and gate to smitherines and the sappers have razed all breach points in the walls, THEN send in your troops, full force and simultaneously.

The trick to a siege is assaulting on multiple fronts. That's why cavalry can be such a valuable asset. Never EVER launch your assault until all sapper's breaches have been achieved/rams have punched in their holes/onagers have demolished their targets. Have patience and wait for all your gaps to be opened then throw your troops through them all; overwhelm and surround your enemy. Cut them off, ride them down, intercept them, but most importantly, hit them as two fists (or more) at once.

But onagers can be detrimental in their cumbersome gaits so if you're traveling across extremely hostile land don't bother with them. They come in handy but they can cause trouble for you too. I love them personally, but that's just me.

So, to answer your question: I believe in both. Onagers work on fortifications, on-site siegecraft work on walls. They are both essential (for me).

Personally, I rarely bother with taking out the towers of Wooden-walled settlements. They have a limited range and field of fire. I prefer to use my Ballistas to take out units. One bolt will take down several members of any unit (my best was a general and three bodyguards with a single bolt). Multiple HP units and Heavy Infantry are the best targets, as they are the ones that take the longest to chew through. If you remove a lot of them before the battle, then you will vastly reduce the losses that you take within the settlement.

I like to have a mix of ranged and on-site equipment, 2 Onagers will destroy a gatehouse and gate comfortably and with three i usually try to trap enemy infantry on the walls by damaging wall sections either side of them, but there is a fatal flaw with bringing both sets of siege equipment and that is never set the Onagers to auto fire or the incinidery ammuntition while commanding your siege towers, once when i was trying to speed a siege up i was using Onagers on the gatehouse whilst my towers advanced either side, all of a sudden Boom! one of my towers is down and the other 54% damaged all because the Onagers decided to change targets after the gate was down and started hittng the towers.

You could always put your onagers into a separate force and initiate the assault with them, with your main atack coming on as reinforcements. Eg if you had 26 units in total of which 6 are onagers, attack with those. 14 units from your stack of 20 will then come on. Your onagers blast the defenders on the walls till they're out of ammo, and the 14 units of your main stack dissuade the defenders from sallying. You then have your 6 onagers retreat. 6 replacement units then come on from your other army and hey presto, you have your full stack again, and hopefully either big holes in the walls or lots of siege equipment.

I do this with skirmisher units sometimes. Once they've expended their ammo it can be usefult o have them withdraw and be replaced by fresh units.

Very good point, Spurius Dufus, that would work very well if you had the Onagers close enough. Personally, I wouldn't do it with Onagers, but I do do it with Archers, since I never go inside the walls of a Wooden Walled settlement until either the enemy are cowering out of range or I am out of arrows.

This would depend on the defensive capabilities of the town.

Is the Wall, stone, or Large stone, or just a wooden palisade? (Large stone, siege towers, Sap points and Heavy Onagers.

Is the Garrison force much less than mine? Did I catch them off guard?(If I catch them off guard and without reinforcements then I want it to be a quick, same turn assault.)

Did my spy successfully open the door?(No point in blowing out the walls and doors if I'm allowed in.)

Well I use onagers sometimes (rarely actually) to attack stone walls and destroy the wall that the enemy are standing on. And by the way Yakcamkir, how do you use ballisae so well, I only get like 7 guys.

Turn off the flame. It makes them much more accurate (same for all missile units that can use flame) and be patient. Wait until the enemy stop moving and then fire. Moving the Ballistas to get the right angle (through the hole you just punched in the wall for example) is well worth it, since it stops so many bolts from hitting the walls.

In all cases, it's a case of my strategy type 1 for taking wooden-walled towns:
1. Make holes in the walls.
2. Shoot the enemy to pieces (this should have over 50% of the enemy dead and end when either you run out of ammunition or the enemy retreat out of range).
3. Enter the town and draw the enemy back into missile range (if you have ammo left).
4. You should now have double the number of troops the enemy has. Butcher them.

I was just using the six foot bolts like most people use arrows. I'm not by any means the first person to think of it, but it really does work.