Allen's magic is capable of killing Ottar if he is not serious. Ottar's magic is equal to Bell's Argo-Vesta, which in turn, when fully charged, increases Bell's attack power by 3 levels (presumably).

5+3 = a maximum level 8 attack.

Ottarl is a level 7 though. Does his magic simply strengthen that attack of his or does it act similar to hell kaios?

Is allen's also an enchantment or an attack magic cause it is a self buff type spell

Ottar's magic is an enchantment, but it strengthens only one attack. Also, when Ottar prepared to defend himself against Allen's magic he only changed his position so he could use his full strength, he never recited Hildis Vini's chant. So using Hildis Vini as a comparison is completely wrong.

Considering Ottar's Strength stat it is minimum a high Level 7 attack. Maybe higher.

Allens Magic greatly increases his speed, the magic itself might also increase his Atk power, but then he also probably has a passive skill where his speed increases his atk power, so the spell scales very well with his kit. Combine that with the potential DA spearman, his damage output is insanely strong so much that Ottar respects it.

• Those of course are added assumptions about his other abilities, but regardless Ottar respects it and he is a maxed End level 7 with the Strong Body DA at level G. That says something about its power.