Mephistopheles

Being the game’s mascot, Mephi’s kit comes in full blast, with most whales pulling for her origin 5 star on day 1. On paper, Mephi is an AoE burst mage that obliterates backlines with her M1 and Ult, especially during analysis mode. It is quite common for a hyper-invested Mephi to OHKO backlines on crit for the earlier stages, with this damage increasing even further at 201 when her ult gives her a 50% attack boost, which creates a mini combo of ult into M1 for tons of damage.

However, she is also one of the game’s best offensive debuffer/buffer at the moment (humanlike unit kits are looking very stacked on release indeed). With crit buff, stun for 8s+increased crit dmg, and defense down, she can vastly improve your entire team’s DPS. 

Her glaring weakness currently is shared amongst most backlines, which is her squishiness and susceptibility to assassins like Jaqueline and Linzy, where a single M1 or a few autos can shut her down. Also, her targeting in a straight line for both M1 and S1 can be problematic, as it sometimes only hits the enemy tank without touching the backline if they are misaligned, which can be a massive DPS drop in story stages. Lastly, her M1 and ult do noticeably reduced damage when not used in analysis mode, so players may have to manual her skills to bring out her full use as a DPS AoE mage.

Combining everything together, she might not fit into some story stages when the enemies are heavily composed of tanks and assassins, without giving Mephi a backline to eliminate. That said, her passive buffs and debuffs still make her an extremely powerful human mage in the current meta.

Single Bosses

For boss stages, it is not uncommon to see top scorers in Chloe boss stage using Mephi for insane numbers like 60m++, even though her personal DPS is not as high as the other hyper carries. This is due to her kit having multiple effects that raise the entire team’s damage, namely, crit buff, DEF down, and increased crit dmg taken. The only 100m Chloe clear at the moment (granted with a pure origin 5 team) also used Mephi, and for good reasons.

PVP

For PVP, she can deal tremendous damage to the backline as long as she is placed in the correct position since her damaging abilities shoot at a straight line which easily reaches the backline. DEF down on M1 at 181 also softens the frontline for your team to kill faster, while the crit buff allows the RNG to be in your favor. When against assassin comps, it is advisable to bench her since she is extremely squishy.