In the console versions of the Skylanders games, the small colorful globes left behind by enemies or when winning an arena match are called Victory Points. They act as the equivalent of experience points in other games, and are generically named as such when earning them after an Arena Battle in Skylanders: Swap Force. When enough points are collected, the Skylander will gain a "level up" and improve to the next level of power. Leveling up increases the Skylander's maximum health, but doesn't directly increase any other stats or add new abilities.
Stronger enemies and bosses will yield a much greater amount of Victory Points (by making the few globes that drop count for way more points), and defeating an enemy with a Skylander that shares an Element with the current elemental zone dramatically increases the Victory Point yield. Furthermore, as of Swap Force, all Victory Points collected in two-player co-op are given to both players equally, regardless of who collects them.
In Giants, activating Luck-O-Tron Wheels of Experience will provide a small chance for defeated enemies to drop more Victory Points, essentially acting like the Skylander defeated them in a matching elemental zone no matter where they were defeated.
In the Nintendo 3DS version of the series, the Skylanders gain upgrades by leveling up, as well as direct boosts to speed, health, and damage.
Level cap
In Skylanders: Spyro's Adventure, Skylanders can use Victory Points to level up to level 10 - when this level is reached the Skylander's maximum health is increased to double what they had at level one.
In Skylanders: Giants, the maximum level obtainable by Victory Points is 15, allowing for 2.5 times their level one maximum health.
In Swap Force, Trap Team, and SuperChargers, 20 is the maximum level cap, allowing for three times their level one maximum health. In Skylanders: Imaginators, 20 is still the maximum level cap, except for Imaginator Skylanders, who all start out with a level cap of 20 but also get a one level boost to their level cap per unique Sensei Skylander the player summons into their game.
Any additional Victory Points collected after the level cap is reached are lost and don’t count towards additional levels, even when sent to later games with higher level caps.
When a Skylander increases its level to a value that is greater than a level cap of an earlier game, and the same Skylander is used in an earlier game, the Skylander's level will be temporarily clamped to that game's level cap. For example, if you level up a Skylander in Trap Team up to level 20, and if you use that same Skylander in Giants, the Skylander's level in that game will be read as 15 while the Skylander's level is saved as 20.