The Rell build for Support is Radiant Virtue and Glacial Augment. This LoL Rell guide for Support at Platinum+ on 13.23 includes runes, items, skill order, and counters.
Rell Counters
Rellwinslane against...
Win Rate
Matchup Rate
Nautilus
2818 games
5.9%
Shaco
330 games
0.7%
Rellloseslane against...
Senna
2870 games
6.0%
Heimerdinger
272 games
0.6%
Brand
816 games
1.7%
Xerath
1058 games
2.2%
Vel'Koz
420 games
0.9%
Swain
743 games
1.6%
Lux
1783 games
3.7%
Neeko
446 games
Zyra
1139 games
2.4%
Zilean
521 games
1.1%
Seraphine
583 games
1.2%
Pyke
1616 games
3.4%
Morgana
1376 games
2.9%
Karma
1116 games
2.3%
Bard
1276 games
2.7%
Tahm Kench
285 games
Pantheon
367 games
0.8%
Ashe
1019 games
2.1%
Taric
440 games
Nami
1212 games
2.5%
Thresh
3375 games
7.1%
Yuumi
1102 games
Sona
461 games
1.0%
Renata Glasc
1711 games
3.6%
Janna
1764 games
Blitzcrank
2077 games
4.4%
Braum
706 games
1.5%
Soraka
1128 games
Milio
1124 games
Leona
1142 games
Lulu
1642 games
Rakan
3278 games
6.9%
Alistar
2004 games
4.2%
Maokai
483 games