Mythril Chainsaw

The mechanical tools cut faster than the swung ones and trade reach for it. That trade is the whole decision. Clearing forest at ground level, standing close is fine and the speed wins outright. Chopping something awkward, a giant glowing mushroom across a gap or a tree you are reaching for from a platform, the extra reach on the Mythril Waraxe is worth more than the raw rate. Plenty of characters carry both and grab whichever suits the job.

The advantage is not fixed. The more tool speed you stack from armor, accessories and buffs, the more the swung tools claw the gap back, and with a fully optimized mining loadout the axe comes out ahead again. Without that setup, which describes most characters at this point in a run, the chainsaw genuinely is the faster tool.

Mythril and orichalcum are alternates, so a world hands you one and not the other. The Orichalcum Chainsaw is the same tool with different numbers on it and there is no difference in how either plays. Nothing is lost either way.

Godly and Demonic work out even on average output, so take whichever the reforge gives you first and stop feeding it coins. As a tool this is a short chapter. Hallowed and chlorophyte tier axes, and combined tools in the Pickaxe Axe family, arrive not long after and do the same job while freeing a slot, at which point this goes in a chest.