It can be an alternative to Arrows, due to the very similar damage and area of effect.
The main differences are that The Log costs one less Elixir while being unable to target air troops. As such, it might be advisable to bring other splash damage cards to deal with the likes of Minions and Minion Horde.
It can also be an alternative to Zap, as both of them have the same Elixir cost. They can both disarm the charge attacks of Prince and Dark Prince if your elixir is low or if your small units are out of rotation. However, they have slightly different effects when used. The Log will not reset a Sparky, but a Zap will.
An important note is that a well placed The Log can eliminate a Princess up to one level higher than it for a positive Elixir trade of 1.
If placed two or fewer tiles away from the bridge, The Log will damage the Princess Tower.
Remember that despite it being a spell, it can only be placed on the player's side, which reduces its effectiveness in certain situations.
If a unit is walking right on the edge of the river on a player's side, the player can use The Log to push the unit over the river back to the opponent's side. This is a good way to counter slow moving units like Giants and P.E.K.K.A.s.
The Log can be an effective counter to Tombstones. If a Tombstone is at around half health, The Log can be used to attack it. The Log will destroy the Tombstone and the spawned Skeletons.
The Log + Fire Spirits can take out Three Musketeers if The Log is placed correctly. Ice Golem can be an alternative to The Log as it is easier to execute. The Log can stun the Three Musketeers and the Fire Spirits will do damage, while the tanks and slows the troops after it dies, so you can use both these effects to your advantage.
If the opponent places a Royal Giant in the middle, you can place The Log to the left of the Royal Giant which will cause it to be pushed to the crown tower lane and start targeting it instead.
If a Miner is placed very close to the King's Tower you can actually use the side of The Log and push the Miner towards the King's Tower, activating it.
Hog Riders can jump over the Log, but only when they are jumping over the river as well. This means that The Log rarely fails to hit its target.
On 24/8/16, a Balance Update decreased The Log's cast time by 66% and its travel speed increased by 20%.
On 19/9/16, a Balance Update enabled The Log to knock back all ground troops.
This also enabled the log to reset the charge attacks of the Prince, Dark Prince, and the Battle Ram, although the ram was not released at this point.
On 20/10/16, a Balance Update increased The Log's rolling speed and distance, as well as increased its damage by 9%.
On 23/1/17 a Balance Update decreased The Log's damage by 4% and decreased its knockback effect (to 1 tile from 1.5 tiles).
On 13/3/17, the March 2017 Update decreased The Log's damage by 4% and decrease its rolling distance by 0.5 tiles (to 11.1 tiles from 11.6 tiles). On the same day, a bug was discovered where the Log was not able to be deployed on top of buildings. To compensate for this, the rolling distance was restored to 11.6 tiles until the next client update.
On 12/6/17, a Balance Update decreased The Log's rolling distance by 0.5 tiles (to 11.1 tiles from 11.6 tiles).
The Log and the Graveyard are the only spells to have a Legendary rarity.
Unlike other spells, it can only be placed in a player's own territory. However, it wouldn't be beneficial to place it in the enemy's territory even if it could, as a part of its rolling range would simply be wasted.
It is one of two spells that do not have a circular area of effect, the other being the Mirror which has no area of effect. It is the only spell that rolls linearly, and the only spell that is not "launched" which can push back targets.
Just like every other Legendary card except the Miner and the Graveyard, it falls from the sky when deployed.
The card's description hints at it being created by the Lumberjack, apparently due to spilled Rage.
The Log can be seen in the menu picture for Arena 6 (Builder's Workshop) on the bottom left corner. Before The Log was introduced into the game, this log had no spikes on it.
It is one of 2 direct-damaging spell cards in which the description does not contain "Reduced damage to crown towers." but does deal reduced damage to Crown Towers, the other being Poison.
It is the cheapest Legendary card in the game and tied with Zap and Rage for the cheapest spell in the game, at 2 Elixir.