A bit of thought and discussion provocative tip or idk...
I recently learned in a video that in old Minecraft the strengh buff gives +130% of damage.... And it's a plus; it's not x1.3 dmg -- it's x2.3...
The Strength II effect gives a x3.6 damage. That's huge and a crit attack on Iron Golem with a vanilla Iron Sword deals 38 dmg to him.
One of the sources of permanent Strength II buff is an Ender Dragon adventure backpack.
But, sadly, there is probably a reason why this is still in a game and this cheap.... The huge strengh multiplier doesn't work neither with Tinker's range or melee weapons neither with GT weapon.
But still. There is a lot of mods out there that might have endgame weapon that would behave like vanilla sword...
The best example so far that I've found is a IC2 nano Saber. Without Strength it deals 21 dmg; and with -- 76, without a crit. With crit you just one shot a golem.
The Vajra sadly doesn't work and deals 25 dmg either with or without Strength.
If you find anything better leave it here.