How to effectively use quick battles (autobattles)?

psychos, cerberi... I think they'll have too few hit points for that.

Approximately 25 cerberi wipe out 3 archs.

The rule is simple:
1. Include units with multi-attack in the army;
2. Take enough so that neutrals split into as many groups as possible;
3. Test for the minimum number of warriors for a creep both with and without the Spirit of Despair, because, for example, a chaos hydra does not kill three archs without this artifact. On the other hand, it kills 3 angels (neg.) without the spirit and cannot do so with the Spirit of Despair.

Regular hydras are also very good (Dragon Utopia max is taken, I believe, by a group of 8 hydras). This needs to be tested.
Replays of all battles of this kind resemble a replay of a hydra battle for the hive:
1. Regarding speed: neutrals attack;
2. Hydra attacks;
3. Neutrals scatter (split), one stack remains and waits;
4. Our multi-attack stack begins wiping everyone out round by round.
5. The remaining neutrals (when only 1 stack is left) attack and perish.