Spike is in many ways Chases opposite, while Chase is a nice if somewhat meek hero, Spike is an assertive, cruel, aggressive but honest soldier. He is also selfish and violent and never afraid to knock others down if he feels they are in his way. He does share some traits with Chase however as both of them have leadership qualities and both are quite cocky.
Spike also shares all of Chases powers and martial arts skills, but unlike Chase he's got no problems exploiting them for his own selfish gain. Due to this and his aggressive tendency's Spike is feared by Chase's siblings, and often panic when ever he emerges.
Despite this, Spike also does have some honor to the Lab Rats, and other people who have earned his trust. He even called out Terry Perry for not helping her team out.