When cast, The Log rolls through the Arena, dealing damage to any troops in its path and disintegrating after rolling for 11.6 tiles.
Any ground troops in the way will be pushed back by The Log.
As a cheap spell, The Log can be used to damage and push back multiple ground troops that come in your way, such as Barbarians or Goblins.
The pushback mechanic is similar to the Fireball, but all troops are pushed back.
It can be used as a counter to the Goblin Barrel, but it may be better to use other cards for this.
It can be an alternative to Arrows, due to the very similar damage and radius.
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.
Note that The Log will not reset a Sparky while 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.
If placed at the edge of the bridge, The Log can damage Arena Towers with reduced damage.
Remember that while it is 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.
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.