Idea of Evil vs The Didact: who would win?

The Didact favored — Favored (~65%)

Idea of Evil · Berserk · Base

Tier
LOW 5-B
Attack Potency
Small Planet Level
Speed
Massively Hypersonic, up to Omnipresent
Durability
Large Mountain Level

The Didact · Halo · With extensive Forerunner technology and/or starships

Tier
5-C
Attack Potency
Moon Level+
Speed
Massively Ftl+
Durability
Moon Level+

A heuristic estimate from normalized VS Battles Wiki stats: tier, attack potency, speed and durability.