One of the most annoying defensive/offensive structure is the Aramonian Trebuchet and all of the five kingdoms (Veruna, Zhon, Creon, Taros, even Aramon) have a problem dealing with them. I have already posted strategies of how to destroy them with each one of the kingdoms, but here are some general tips which I hope will help to deal with them, no matter what your kingdom is.
1] When you see your ground units or structures to be hitted by something that looks like an extremely-fast moving cannonbal it is by 95% a Trebuchet. The first thing you should do is to detect the way from where that "cannonball" came. It is not an easy thing to detect its coming direction, you actually can only notice the moving Trebuchet's projective just before it hits you, but you must!
2] After detecting its direction, quickly create an aerial scout and send it flying towards the Trebuchet's direction. Sooner or later, you will notice a big wooden structure with a round stone base. This is the Trebuchet. If your aerial scout is killed by Archers or something else before you locate the structure, make a few more aerial scouts and send them all together. Luckily, someone will survive to see the Treb's location.
3] Deal with the problem! Destroy the Trebuchet!! This may be an easy or an extremely difficult task, depends on how well the Aramonian player guards this engine of destruction. The most common way is to create a dozen of very fast ground melee or ranged units and send them alltogether against the Treb. Another way is by using your siege ranged units and destroy it from distance (less than a dozen is required here).
4] In case the upper strategy doesn't work because the Aramonian ground defenses are too strong (many Strongholds or a lot of infantry for example) or because the terrain makes it impossible (aquatic maps for example) you should create a dozen of offensive flying units and make an air attack against the Trebuchet. However, groups of Aramonian Guard Towers and Mage Archers are excellent air fleet killers, so beware!
5] If you play on an aquatic map and the enemy has built an Aramonian Trebuchet near the coast, you can perform a surprise naval attack. Bombard the Treb with powerful offensive ships, if it is on their range, and use weaker ships to upload troops on shore at the same time.
6] If you can build long-range offensive structures, then build one as fast as possible using multiple builders, protect the builders with a few troops and make sure your opponent would not spot your recently-constructed structure by preventing aerial scouts to reach it. If your opponent sees your structure in time, he/she may bombard it with the Trebuchet itself, so all your effort, time and mana will go to waste. You should also be sure that the Treb is within range of your offensive structure, cause it would be a shame to build it and to be unable to strike your nemesis with it.
7] If you have an aerial transport, a good strategy is to upload melee ground units on it, to fly across the sky and to download them adjactent to the Aramonian Treb. Then, attack your target with all the melee units.
8] Ruining a Trebuchet with your monarch is a dangerous task, but it can be useful at sometimes. Be careful, though, not losing your morarch through the progress. Remember, you cannot build a monarch and it would be a shame to die by your opoonent's defences because of a silly Treb.
9] Here is some extra info about the trebuchet:
* Trebuchets cost more than 10000 mana and are slow in production, so if you destroy it before it act your opponent will lose a lot of time and a lot of mana for nothing!
* Trebuchets have tremendous range! In small maps, they can easily hit any ground/naval unit or building. However, they cannot hit aerial units and in big maps you can keep your ground/naval units safe by leading them out of the Treb's range.
* Trebs are rediculously fragile. It is by far the Aramonian building with the less hit points (if you exclude Lodestones), so they can be destroyed really fast.
* Search every single inch of the map for hostile Aramonian Trebuchets. You never know where they might be...
Subject: How to deal with the Aramonian Trebuchet. 
