You can bless ankhs even with Barren Land by throwing waterskin into a healing well and that fills it up to 20/20.
Ascending with the amulet grants you more score multiplier that makes the 1 million score much more easy to reach.
You probably had the million score run here by just doing On diet and by ascending. Ascending is quite easy if you just keep the amulet curse green by killing a few enemies every floor. Every boss floor while ascending also heals you to full health and people tend to forget that.
I recommend giving Horn of plenty some love if you find it as it makes On diet very easy.
You can for example combine snacking from horn of plenty with warrior iron stomach +2 to completely negate many of the strong attacks. For example Evil eye lasers, Yog Lasers and Tengu bombs.
Snacking from horn is crazy on Rogue too as you pretty much get infinite cloak charges with tier 2 perk mystical meal +2 that gives you 5 turn of artifact recharging.
On Mage you can use the horn with energizing meal +2 that gives you 8 turns of wand charge and just combine that with shield battery +2 for huge shielding.