I think the most helpful troop as reinforcements is Dragon or Valkyrie. What do you think about it?

Valkery is good is think it does lots of damege arond her

hog rushing is the best

Dragon is better than Valkyrie

The effectiveness of reinforcement troops during clan wars depends on the troops used by your enemy when attacking your base.
However, the most commonly used reinforcement troops used in clan wars is the dragon, the valkyrie and the wiz-arch combination.
The dragon can be very helpful because of its ability to attack both air and ground targets.
It is also a good reinforcement troop because it can target a group of enemy at a time killing multiple targets at a time.
The dragon can be used as reinforçement troop for both offense and defense.
The valkyrie is a popular reinforcement troop for beginner players whose attacks are composed of an army of barbarians, archers and giants because it can only attack ground troops.
It has a high hit points which makes it difficult to kill and can attack multiple targets within its range.
The valkyrie is a good reinforcement troop for defense but not an effective one for offense.
Another good combination of reinforcement troops for defense id the wiz-arch combination composed of obviously wizards and archers.
This kind of combination is also popular in players on town halls level 9 and 10 using ground attacks.