D&D Beyond - Dungeons & Dragons Fifth Edition Tools, Rules, Races, Classes, Items, Spells, Monsters, and More
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so after going nuts for hours inbetween doing work (my boss thinks just because she pays me I am supposed to do things) that the basic rules on monster uses acolyte CR 1/4 and Archmage CR 12 as examples:
so CR 1/4 is perfect for your 1st level character to face with save DC 12
a CR 12 is perfect for your 11th level character to face with a save DC 17
so we have MONSTERS.... grrr
a character has 6 saves useing the defualt array +2/+1 that gives them lets say
16, 16, 13, 12, 10, and 8 again not perfect but not bad... that next lets put a 16 in a prof save stat and 1 16 in a non prof save stat... but put the 13 in the other prop save stat.. that makes our saves +5 +3 +3 +1 +0 -1
11th level... and say the one making the saves is a rogue or fighter so 3 stat ups... making it 20 16 14 13 10 8 with prof of +4 and I will give +1 magic to all saves... so +10, +7, +4, +2 +1 +0
the monster DC went up 5, and how did the players fair? best save went up by 5 so you did not get better but you didn't get worse, your second 1 goes up by 4 so you need 1 higher on the D20, after that it does not look good at all, 3rd best save went for +3 to +4 so only up by one for a net -4... at 1st level you would save onn a 9 or better and now you need a 13 or better... and that is your 3rd best save... lets jump to the end and look at your worst... it went up by 1 you need a 13 before you need a 17 now...
now back to the no stat bumps but 3 picks in reseliance redone without forgetting... so stats of 16 16 13 12 10 8 the 16 and 13 prof I can make some more prof and add +1 lets make the 8 10 and other 16 prof... so new stats 16 17 13 12 11 9 giving saves of +8 +8 +6 +2 +5 +4 for best saves in the possible but remember the DC went up by 5 so we now net -2 to the prime stat save +5 to your other highest then back to got worse (but less so on all of them...
if prof was given to all saves as hamerman said we get a bit better but still not really keeping up (prof is 2pts higher magic is 1 so over all if you are not upping the stat it just doesn't keep up)