Caulder, ベリス (Berisu Berith) in the unreleased Japanese version (Famicom Wars DS: Ushinawareta Hikari), is the main antagonist of Advance Wars: Days of Ruin.
In Dr. Caulder's youth, cloning technology has advanced a lot, but wasn't used for ethical reasons. Caulder threw ethics aside and made multiple clones and performed inhumane experiments on them, which caused the clones to rebel and have a bloody war. In the end, only one clone remained, and that was the Caulder that became the Leader of Intelligent Defense Systems. Caulder then took the name of his creator, created four clones of him as his children (Tabitha, Penny, Cyrus, and Isabella), and supplied Lazuria and Rubinelle with weapons of mass-destruction.
After the Meteor strikes, Isabella was separated and joined 12th Battalion in the midst of a battle between The Beast's Raiders and Brenner's Wolves. After this Caulder, supplied The Beast once his raiders were destroyed, but after his final defeat, Caulder kills him. Caulder is then seen supplying the Lazurian Army, but General Forsythe refuses to use them. After the defeat of the New Rubinelle Army, Caulder sends his kids in The Great Owl to destroy 12th Battalion and take Isabella back. After Penny's defeat, Caulder reveals that Isabella is his clone child which turns public opinion against her, and she defects briefly and joins caulder. After Tabitha's defeat, Caulder decides his children are useless, and orders Penny to kill herself and Isabella and the other passengers of The Great Owl by crashing it. However, Isabella convinces her otherwise, and Isabella and Penny join with 12th Battalion. Caulder then forces Cyrus to drink poison, and while he's dying, he defects and tells 12th Battalion where the cure to the Creeper is, but dies shortly afterwards.
Caulder stays at The Nest, a giant factory-weapon. During the battle he tells about him being clones. He is killed in the destruction of The Nest.
All units receive a large attack and defence boost, and regain 5 HP
- He was removed from multi-player in the US version before the game even came out, thus banned from competitive gameplay.
- He is the one of the only 2 COs who does not have a CO Power, alongside with Forsythe. This is due to the fact that his CO ability is extremely impressive (in comparison to the other COs' abilities), therefore giving him a CO Power would be considered rather unfair.
- He is one of only 2 COs in the Advance Wars series that can heal 5 HP for his units, the other being Andy.
- He is the only character to have died immediately after the end of a battle.