Tier 5:
Prefix: "Tera"
Suffix: "za"
"Fireza", "Teradeath"
Tier 6:
Prefix: "Peta"
Suffix: "(e)xa"
"Firexa", "Ultimaxa", "Petadeath", "Lightexa"
Basic elemental spells end here.
Tier 7:
Prefix: "Exa"
Suffix: "ma"
"Exadeath", "Meteorma"
Few handfuls of spells.