Aggradon Lancers - Spears v Clubs

I have some Aggradon Lancers on the way, and rather like the Saurus Warriors, the question arrises should they be built with Spears or Clubs?

The maths here is slightly different. The significant differences between Warrior spears and clubs are that the spears hit on 4+ with 2" range, rather than 3+ and 1 inch range for the clubs. Both weapons have a rend of -1. As the warriors come in a minimum unit size of 10 on a 32mm base the 2 inch reach could be quite important as it allows getting more warriors into combat.

For the Lancers, clubs hit on 3+, wound on 3+, with rend -1 and a 1" reach. Spears hit on 4+, wound on 3+, with a 2" reach and a rend of -2.

For clubs, the expected damage from the riders looks like this:

Expected Damage from Aggradon Lancers armed with Celestite Clubs against various armour saves
Save 2+ 3+ 4+ 5+ 6+
Model Count
1 0.4 0.7 0.9 1.1 1.3
2 0.9 1.3 1.8 2.2 2.7
3 1.3 2.0 2.7 3.3 4.0
4 1.8 2.7 3.6 4.4 5.3
5 2.2 3.3 4.4 5.6 6.7
6 2.7 4.0 5.3 6.7 8.0
7 3.1 4.7 6.2 7.8 9.3
8 3.6 5.3 7.1 8.9 10.7
9 4.0 6.0 8.0 10.0 12.0

And for spears it looks like this:

Expected Damage from Aggradon Lancers armed with Celestite Spears against various armour saves
Save 2+ 3+ 4+ 5+ 6+
Model Count
1 0.5 0.7 0.8 1.0 1.0
2 1.0 1.3 1.7 2.0 2.0
3 1.5 2.0 2.5 3.0 3.0
4 2.0 2.7 3.3 4.0 4.0
5 2.5 3.3 4.2 5.0 5.0
6 3.0 4.0 5.0 6.0 6.0
7 3.5 4.7 5.8 7.0 7.0
8 4.0 5.3 6.7 8.0 8.0
9 4.5 6.0 7.5 9.0 9.0

Spears will maintain their effect better than clubs at model counts greater than 6 due to a 2" reach, but the effect is unlikely to be as profound as with Saurus Warriors.

What's probably of most interest is the comparison:

Expected excess damage for Aggradon Lancers armed with Spears, over Clubs, at various armour saves

The take home message appears to be that if you're expecting to face lots of units with a save of 2+ (the green zone, would would include units with a native save of 3+ with a bonus to the roll such as all out defence or mystic shield) then spears beat clubs. If you're expecting saves of 4+ or worse (including modifiers - the red zone) then clubs beat spears. At 3+ it doesn't make any difference.

The disadvantage in the green zone is however small. A unit of 3 Lancers with clubs against a 2+ save would do, on average, 0.2 fewer wounds compared to using spears. That's a reduction from 1.5 to 1.3 expected wounds, or about 13%.

This does only consider the rider's attacks. The base profile of the mount looks like this, but will not change with the riders' weapon choice:

Expected damage for Aggradon Lancers armed with Rending Bites and Striking Talons, at various armour saves, at rage level zero
Save 2+ 3+ 4+ 5+ 6+
Model Count
1 0.9 1.3 1.8 2.2 2.7
2 1.8 2.7 3.6 4.4 5.3
3 2.7 4.0 5.3 6.7 8.0
4 3.6 5.3 7.1 8.9 10.7
5 4.4 6.7 8.9 11.1 13.3
6 5.3 8.0 10.7 13.3 16.0
7 6.2 9.3 12.4 15.6 18.7
8 7.1 10.7 14.2 17.8 21.3
9 8.0 12.0 16.0 20.0 24.0

So considering the entirety of the attack profile the deficit from using clubs rather than spears against a save of 2+ is a reduction from a total of 4.2 wounds to 4 wounds: approximately 5%. There is a lot of upside from using clubs against saves of 4+ or worse, and no difference if the required roll is 3+.

So spears are superior against very elite armies with good armous saves, especially if they can issue all out defence multiple times. Clubs will be superior otherwise.

I think I'll be going with clubs. Your meta may vary.