Water balloons are Calvin's favorite summertime weapon, much like he favors snowballs during winter. Originally, he used his Water Gun, but it fell out of favor in the face of water balloons' superior power.
Warfare
Calvin often engages in water balloon fights with Hobbes. Although Calvin will put more effort behind soaking his adversary, he inevitably loses due to his habit of boasting. For instance, he once walked up to Hobbes with three water balloons, making much noise about his superior armament. Hobbes then dropped his own water balloon into Calvin's hoard, giving him no choice but to throw them all at once without aim.
Once, Calvin invited Susie to a water balloon/water gun battle; Hobbes surrendered his balloon to the enemy, and Calvin lost yet again.
Ambush
When not battling at Hobbes' consent, Calvin still mounts offensives with his water balloons. These attacks are directed primarily at Susie and Hobbes, although Calvin has also soaked his parents on a few occasions.
Hobbes does not take these ambushes well, possibly given his fur coverage. He usually manages to dissuade Calvin from ambushing him, foretelling of punishment unequaled should Calvin dare attack him.
Calvin is far more inclined to soak Susie Derkins than Hobbes, due to her (official) status as his enemy. In order to to do, he will not only plan traditioal ambushes, but also traps and mechanisms.
"It'll build character!"
This article is a stub. You can help the The Calvin and Hobbes Wiki by expanding it.