Genshin Impact currently has six different catalyst users across five Elements. This makes listing the top five reasonably easy, since one of these characters isn't all that great. With new catalyst users on the horizon, this list will undoubtedly change in the next few months.
Genshin Impact Top 5 catalyst characters
#5 - Barbara
"Every citizen of Mondstadt adores Barbara. However, she learned the word 'idol' from a magazine."
Birthday: July 5th
Barbara is probably the first healer most players ever receive, given how Genshin Impact seems to love giving her away for free. This makes her an invaluable asset to any team composition for new players. It is also almost impossible to hate Barbara, even with miYoHo changing her voice lines recently.
#4 - Sucrose
"An alchemist filled with curiosity about all things. She researches bio-alchemy."
Birthday: November 26th
When powered up, Sucrose is pretty impressive with an Elemental Burst similar to Venti's with how it pulls in nearby enemies. She is excellent at crowd control and gathering foes for a player's DPS or other Utility to take down with raw DMG or Swirl damage.
#3 - Ningguang
"The Tianquan of Liyue Qixing. Her wealth is unsurpassed in all of Teyvat."
Birthday: August 26th
Constellation: Opus Aequilibrium
Ningguang is Genshin Impact's queen of AoE damage, firing blasts of Geo that can also mine ore or shatter shields. Her Jade Screen provides defensive support while also adding additional damage when her Elemental Burst is used. All players need to focus on is buffing her Crit & and CritDMG to have a severe powerhouse on their hands.
#2 - Mona
"A mysterious young astrologer who proclaims herself to be "Astrologist Mona Megistus," and who possesses abilities to match the title. Erudite, but prideful."
Birthday: April 31st
Mona makes a fantastic sub-DPS with quick attack speed, significant damage output, and a catalyst user's range flexibility. She pairs exceptionally well with Genshin Impact characters like Keqing and Qiqi, playing off their elements well to rack up additional damage.
#1 - Klee
"An explosives expert and a regular at the Knights of Favonius' confinement room. Also known as Fleeing Sunlight."
Birthday: July 27th
Klee is Genshin Impact's feisty powerhouse. As one of the best DPS characters in the game, Klee pushes out Pyro DMG like it is going out of style. Combined with her Elemental Burst and how well Pyro stacks, there is no denying Klee is the best catalyst user in Genshin Impact.