Frost Giants are a special unit in Stronghold Legends, and only available to players who are currently playing as the Ice faction.
They are recuited from The Ice Tower, costing 200 gold and 100 honour. You can find out ways to generate Honour in the game here.
This massive cost, however, should not be thought of too harshly. Frost Giants are perhaps one of the most powerful and overbearing units in the entire game, certainly on ground level.
Their immense damage can obliterate castle defences, destroy armies and cause utter chaos to buildings and structures placed on a map.
Combined with a fast movement speed, all this makes the Frost Giant an exceptional force to be reckoned with on the battlefield.
Frost Giants are not only incredible at attacking enemy units, but they also take in hardly any damage from enemy units as well. This means that you will need a considerable group of units to kill a Frost Giant.
When combined in numbers, Frost Giants are a truly unstoppable force on the battlefield and will win outright in virtually any skirmish because of their large attack strength. Frost Giants have a number of varying attacks, from stamping on enemy units to smashing their club down on the ground at them. This attack will send all enemy units in the Frost Giant's vicinity flying, knocking them backwards and damaging their health.
Not only does this damage the health of any attacking units, it also scatters them over an area and prevents them from quickly being able to attack the Frost Giant again. This allows the Frost Giant to focus on one or two of these units specifically and provide the maximum damage to them before the others can catch up again.
Any enemy units that are knocked back into trees, water or other impassable terrain by the Frost Giant's club attack will be removed from the map. Their fast movement speed means that they are very well placed to attack estates early on in the game, or to re-capture them from enemy units.
Their strength in both attacking and defending means that it's unlikely they will be massively damaged in taking back and enemy estate, and you can then send more reinforcements to the estate once it has been captured.
Frost Giants are great for quickly arriving at areas and defending choke points or supporting other units against bigger armies to hold your ground. They can also attack walls, towers and gatehouses directly, without any need for Siege Equipment. The Frost Giant will simply walk up to an enemy wall and start obliterating it, similar to Polar Bears, only Frost Giants do far more damage and in a shorter time.
The Frost Giant will swing his club and bash it at the wall, knocking any enemy units stationed there flying backwards to the ground. Not only does this deplete their health, it also removes them from the wall entirely, often putting them out of range so they cannot continue to attack, and allows the Frost Giant to continue attacking the wall unaffected by the defenders. Any siege weapons placed on the wall (such as Wall Mounted Rolling Logs) will be automatically removed from the wall as soon as the Frost Giant first hits the wall with his club.
It goes without saying that if you are playing against a player using Frost Giants, you should place an Engineer's Guild in your castle to try and automatically repair and slow down any damage caused by them to your walls before it gets worse. Note however that Frost Giants cannot scale walls or towers, or reach the Lord on the top of an enemy Keep.
They cannot move from ground level throughout the entire game, so while they can destroy an entire castle and all buildings and units at ground level on the map, they cannot win you the game on their own unless an enemy Lord wanders down from the Keep to ground level, in which case he can be attacked.
However, Frost Giants cannot defend themselves against aerial attack in any way, and this is their real downfall. They also cost a great deal in both honour and gold to consistently keep recruiting, unless you have a substantial resource advantage compared to your opponents. White Witches deal very little damage against Frost Giants alone, but in a large group and with time, they can be used to take out Frost Giants in advance of them arriving at your own castle to avoid the problems that will undoutedly arise.
Tip: There is virtually no strategy that can prevent the mass-use of Frost Giants to destroy your castle and army, other than using Frost Giants to fight them off. If you are playing as an Ice faction, you can also place Ice Mirrors on your wall or use the Ice Queen to freeze them to buy more time to dipose of them, but they are very difficult to deal with.
Use them as ideal harassment units to look for problems in enemy defence systems, and later on in the game, they can also be used in numbers to even better extent in a combined siege effort to destroy enemy walls. Once you have destroyed an enemy castle, destroy their Barracks, Armoury and all other military production buildings, and you have essentially destroyed that opponent. Frost Giants will not disappoint you.