Board Thread:Questions and Answers/@comment-27327020-20160404174206/@comment-5498154-20160504012631

I'd say, from strongest to weakest:

Chara

Asriel

Amalgamates (Lemon Bread, Reaper Bird, Endogeny, Memoryhead, Snowdrake's Mother, in that order)

Box Mettaton

Frisk

Sans

Undyne the Undying

Photoshop Flowey

Asgore

everyone else...

Flowey (NOT Photoshop Flowey)

Mettaton NEO

Alphys