diff --git a/.gitignore b/.gitignore
index 1e3381d2..18d9cb85 100644
--- a/.gitignore
+++ b/.gitignore
@@ -55,3 +55,7 @@ __pycache__/
 /docs/cheatsheet/*
 !/docs/cheatsheet/cheatsheet.tex
 /docs/testServe/
+
+# Jet Brains
+.idea
+*.iml
diff --git a/CHANGELOG.md b/CHANGELOG.md
index ba5f4da2..84a7a35a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,9 @@
 - **FIX**: delay when opening docs
 - **FIX**: `PROB 100` would only execute 99.01% of the time.
 - **FIX**: some `G.FDR` configurations caused incorrect rendering in grid visualizer
+- **NEW**: `PROB` accepts an `ELSE` condition
+- **NEW**: alias `PRB` for `PROB`
+- **NEW**: new op: `WTOSS`, alias `WT`
 
 ## v4.0.0
 
diff --git a/docs/ops/controlflow.toml b/docs/ops/controlflow.toml
index 1a704ef9..97ad8c4e 100644
--- a/docs/ops/controlflow.toml
+++ b/docs/ops/controlflow.toml
@@ -60,7 +60,7 @@ short = "if all previous `IF` / `ELIF` fail, and `x` is not zero, execute comman
 
 [ELSE]
 prototype = "ELSE: ..."
-short = "if all previous `IF` / `ELIF` fail, excute command"
+short = "if all previous `IF` / `ELIF` fail, execute command"
 
 [L]
 prototype = "L x y: ..."
@@ -155,7 +155,13 @@ Negative numbers will synchronize to to the divisor value, such that `SYNC -1` c
 
 [PROB]
 prototype = "PROB x: ..."
+aliases = ["PRB"]
 short = "potentially execute command with probability `x` (0-100)"
+description = """
+If `x` is within probability execute command.
+
+The `ElSE` / `ELIF` statements can follow PROB on subsequent lines to operate as a Bernoulli gate of sorts.
+"""
 
 [SCRIPT]
 prototype = "SCRIPT"
diff --git a/docs/ops/maths.toml b/docs/ops/maths.toml
index a8738844..11603b37 100644
--- a/docs/ops/maths.toml
+++ b/docs/ops/maths.toml
@@ -38,6 +38,11 @@ short = "generate a random number between `x` and `y` inclusive"
 prototype = "TOSS"
 short = "randomly return `0` or `1`"
 
+[WTOSS]
+prototype = "WTOSS x"
+aliases = ["WT"]
+short = "return `0` or `1` based on a weighted probability of `x` (0-100)"
+
 ["?"]
 prototype = "? x y z"
 short = "if condition `x` is true return `y`, otherwise return `z`"
@@ -365,7 +370,7 @@ N.B 2 R101011010101   ==>  set scale to D-major
 CV 1 N.B 3            ==>  set CV 1 to 3rd degree of scale
                            (F#, value corresponding to N 6)
 N.B 3 R100101010010   ==>  set scale to Eb-minor pentatonic
-CV 1 N.B 2            ==>  set CV 1 to 2nd degree of scale 
+CV 1 N.B 2            ==>  set CV 1 to 2nd degree of scale
                            (Gb, value corresponding to N 6)
 N.B 5 -3              ==>  set scale to F-lydian using preset
 ```
@@ -454,7 +459,7 @@ Chords
  - `11` = Minor 6th `{0, 3, 7, 9}`
  - `12` = 7sus4 `{0, 5, 7, 10}`
  """
- 
+
 ["N.CS"]
 prototype = "N.CS r s d c"
 short = "Note Chord Scale operator, `r` is the root note (`0-127`), `s` is the scale (`0-8`), `d` is the scale degree (`1-7`) and `c` is the chord component (`0-3`), returns a value from the `N` table."
@@ -472,7 +477,7 @@ Chord Scales - Refer to chord indices in `N.C` OP
  - `7` = Myxolidian `{6, 0, 1, 1, 0, 2, 1}`
  - `8` = Locrian `{6, 0, 1, 1, 0, 2, 1}`
  """
- 
+
 [V]
 prototype = "V x"
 short = "converts a voltage to a value usable by the CV outputs (`x` between `0` and `10`)"
diff --git a/docs/ops/seed.toml b/docs/ops/seed.toml
index 8301af14..c7a330dc 100644
--- a/docs/ops/seed.toml
+++ b/docs/ops/seed.toml
@@ -13,7 +13,7 @@ short = "get / set the random number generator seed for `R`, `RRAND`, and `RAND`
 prototype = "TOSS.SEED"
 prototype_set = "TOSS.SEED x"
 aliases = ["TOSS.SD"]
-short = "get / set the random number generator seed for the `TOSS` op"
+short = "get / set the random number generator seed for the `TOSS` and `WTOSS` ops"
 
 ["PROB.SEED"]
 prototype = "PROB.SEED"
diff --git a/docs/whats_new.md b/docs/whats_new.md
index 4bb40176..b03f8454 100644
--- a/docs/whats_new.md
+++ b/docs/whats_new.md
@@ -5,6 +5,9 @@
 - **FIX**: delay when opening docs
 - **FIX**: `PROB 100` would execute only 99.01% of the time.
 - **FIX**: some `G.FDR` configurations caused incorrect rendering in grid visualizer
+- **NEW**: `PROB` accepts an `ELSE` condition
+- **NEW**: alias `PRB` for `PROB`
+- **NEW**: new op: `WTOSS`, alias `WT`
 
 ## v4.0.0
 
diff --git a/src/match_token.rl b/src/match_token.rl
index b0cdd6a6..d922a7b8 100644
--- a/src/match_token.rl
+++ b/src/match_token.rl
@@ -204,6 +204,8 @@
         "R.MIN"       => { MATCH_OP(E_OP_R_MIN); };
         "R.MAX"       => { MATCH_OP(E_OP_R_MAX); };
         "TOSS"        => { MATCH_OP(E_OP_TOSS); };
+        "WTOSS"       => { MATCH_OP(E_OP_WTOSS); };
+        "WT"          => { MATCH_OP(E_OP_WT); };
         "MIN"         => { MATCH_OP(E_OP_MIN); };
         "MAX"         => { MATCH_OP(E_OP_MAX); };
         "LIM"         => { MATCH_OP(E_OP_LIM); };
@@ -225,7 +227,7 @@
         "OUTR"        => { MATCH_OP(E_OP_OUTR); };
         "INRI"        => { MATCH_OP(E_OP_INRI); };
         "OUTRI"       => { MATCH_OP(E_OP_OUTRI); };
-	"NZ"          => { MATCH_OP(E_OP_NZ); };
+	    "NZ"          => { MATCH_OP(E_OP_NZ); };
         "EZ"          => { MATCH_OP(E_OP_EZ); };
         "RSH"         => { MATCH_OP(E_OP_RSH); };
         "LSH"         => { MATCH_OP(E_OP_LSH); };
@@ -897,6 +899,7 @@
 
         # delay
         "PROB"        => { MATCH_MOD(E_MOD_PROB); };
+        "PRB"        => { MATCH_MOD(E_MOD_PRB); };
         "DEL"         => { MATCH_MOD(E_MOD_DEL); };
         "DEL.X"       => { MATCH_MOD(E_MOD_DEL_X); };
         "DEL.R"       => { MATCH_MOD(E_MOD_DEL_R); };
diff --git a/src/ops/controlflow.c b/src/ops/controlflow.c
index 3cfebf69..c3af83ee 100644
--- a/src/ops/controlflow.c
+++ b/src/ops/controlflow.c
@@ -57,6 +57,7 @@ static void op_SYNC_get(const void *data, scene_state_t *ss, exec_state_t *es,
 
 // clang-format off
 const tele_mod_t mod_PROB = MAKE_MOD(PROB, mod_PROB_func, 1);
+const tele_mod_t mod_PRB = MAKE_MOD(PRB, mod_PROB_func, 1);
 const tele_mod_t mod_IF = MAKE_MOD(IF, mod_IF_func, 1);
 const tele_mod_t mod_ELIF = MAKE_MOD(ELIF, mod_ELIF_func, 1);
 const tele_mod_t mod_ELSE = MAKE_MOD(ELSE, mod_ELSE_func, 0);
@@ -86,7 +87,11 @@ static void mod_PROB_func(scene_state_t *ss, exec_state_t *es,
     int16_t a = cs_pop(cs);
     random_state_t *r = &ss->rand_states.s.prob.rand;
 
-    if (random_next(r) % 100 < a) { process_command(ss, es, post_command); }
+    es_variables(es)->if_else_condition = false;
+    if (random_next(r) % 100 < a) {
+        es_variables(es)->if_else_condition = true;
+        process_command(ss, es, post_command);
+    }
 }
 
 static void mod_IF_func(scene_state_t *ss, exec_state_t *es,
diff --git a/src/ops/controlflow.h b/src/ops/controlflow.h
index 5d2477f5..d1a760f8 100644
--- a/src/ops/controlflow.h
+++ b/src/ops/controlflow.h
@@ -4,6 +4,7 @@
 #include "ops/op.h"
 
 extern const tele_mod_t mod_PROB;
+extern const tele_mod_t mod_PRB;
 extern const tele_mod_t mod_IF;
 extern const tele_mod_t mod_ELIF;
 extern const tele_mod_t mod_ELSE;
diff --git a/src/ops/maths.c b/src/ops/maths.c
index 270630b8..f518e5ef 100644
--- a/src/ops/maths.c
+++ b/src/ops/maths.c
@@ -36,6 +36,8 @@ static void op_R_MAX_set(const void *data, scene_state_t *ss, exec_state_t *es,
                          command_state_t *cs);
 static void op_TOSS_get(const void *data, scene_state_t *ss, exec_state_t *es,
                         command_state_t *cs);
+static void op_WTOSS_get(const void *data, scene_state_t *ss, exec_state_t *es,
+                        command_state_t *cs);
 static void op_MIN_get(const void *data, scene_state_t *ss, exec_state_t *es,
                        command_state_t *cs);
 static void op_MAX_get(const void *data, scene_state_t *ss, exec_state_t *es,
@@ -187,6 +189,8 @@ const tele_op_t op_R = MAKE_GET_SET_OP(R, op_R_get, op_R_set, 0, true);
 const tele_op_t op_R_MIN = MAKE_GET_SET_OP(R.MIN, op_R_MIN_get, op_R_MIN_set, 0, true);
 const tele_op_t op_R_MAX = MAKE_GET_SET_OP(R.MAX, op_R_MAX_get, op_R_MAX_set, 0, true);
 const tele_op_t op_TOSS  = MAKE_GET_OP(TOSS    , op_TOSS_get    , 0, true);
+const tele_op_t op_WTOSS = MAKE_GET_OP(WTOSS   , op_WTOSS_get   , 1, true);
+const tele_op_t op_WT    = MAKE_GET_OP(WT      , op_WTOSS_get   , 1, true);
 const tele_op_t op_MIN   = MAKE_GET_OP(MIN     , op_MIN_get     , 2, true);
 const tele_op_t op_MAX   = MAKE_GET_OP(MAX     , op_MAX_get     , 2, true);
 const tele_op_t op_LIM   = MAKE_GET_OP(LIM     , op_LIM_get     , 3, true);
@@ -548,6 +552,13 @@ static void op_TOSS_get(const void *NOTUSED(data), scene_state_t *ss,
     cs_push(cs, random_next(r) & 1);
 }
 
+static void op_WTOSS_get(const void *NOTUSED(data), scene_state_t *ss,
+                        exec_state_t *NOTUSED(es), command_state_t *cs) {
+    int16_t a = cs_pop(cs);
+    random_state_t *r = &ss->rand_states.s.toss.rand;
+    cs_push(cs, random_next(r) % 100 < a ? 1 : 0);
+}
+
 static void op_MIN_get(const void *NOTUSED(data), scene_state_t *NOTUSED(ss),
                        exec_state_t *NOTUSED(es), command_state_t *cs) {
     int16_t a, b;
diff --git a/src/ops/maths.h b/src/ops/maths.h
index bbbbb2e9..72f68937 100644
--- a/src/ops/maths.h
+++ b/src/ops/maths.h
@@ -16,6 +16,8 @@ extern const tele_op_t op_R;
 extern const tele_op_t op_R_MIN;
 extern const tele_op_t op_R_MAX;
 extern const tele_op_t op_TOSS;
+extern const tele_op_t op_WTOSS;
+extern const tele_op_t op_WT;
 extern const tele_op_t op_MIN;
 extern const tele_op_t op_MAX;
 extern const tele_op_t op_LIM;
diff --git a/src/ops/op.c b/src/ops/op.c
index fd8dbbc8..bc299900 100644
--- a/src/ops/op.c
+++ b/src/ops/op.c
@@ -88,9 +88,9 @@ const tele_op_t *tele_ops[E_OP__LENGTH] = {
 
     // maths
     &op_ADD, &op_SUB, &op_MUL, &op_DIV, &op_MOD, &op_RAND, &op_RND, &op_RRAND,
-    &op_RRND, &op_R, &op_R_MIN, &op_R_MAX, &op_TOSS, &op_MIN, &op_MAX, &op_LIM,
-    &op_WRAP, &op_WRP, &op_QT, &op_QT_S, &op_QT_CS, &op_QT_B, &op_QT_BX,
-    &op_AVG, &op_EQ, &op_NE, &op_LT, &op_GT, &op_LTE, &op_GTE, &op_INR,
+    &op_RRND, &op_R, &op_R_MIN, &op_R_MAX, &op_TOSS, &op_WTOSS, &op_WT, &op_MIN,
+    &op_MAX, &op_LIM, &op_WRAP, &op_WRP, &op_QT, &op_QT_S, &op_QT_CS, &op_QT_B,
+    &op_QT_BX, &op_AVG, &op_EQ, &op_NE, &op_LT, &op_GT, &op_LTE, &op_GTE, &op_INR,
     &op_OUTR, &op_INRI, &op_OUTRI, &op_NZ, &op_EZ, &op_RSH, &op_LSH, &op_LROT,
     &op_RROT, &op_EXP, &op_ABS, &op_SGN, &op_AND, &op_OR, &op_AND3, &op_OR3,
     &op_AND4, &op_OR4, &op_JI, &op_SCALE, &op_SCL, &op_N, &op_VN, &op_HZ,
@@ -293,7 +293,7 @@ const tele_op_t *tele_ops[E_OP__LENGTH] = {
 const tele_mod_t *tele_mods[E_MOD__LENGTH] = {
     // controlflow
     &mod_IF, &mod_ELIF, &mod_ELSE, &mod_L, &mod_W, &mod_EVERY, &mod_EV,
-    &mod_SKIP, &mod_OTHER, &mod_PROB,
+    &mod_SKIP, &mod_OTHER, &mod_PROB, &mod_PRB,
 
     // delay
     &mod_DEL, &mod_DEL_X, &mod_DEL_R, &mod_DEL_G, &mod_DEL_B,
diff --git a/src/ops/op_enum.h b/src/ops/op_enum.h
index dad0ed69..9b59bb19 100644
--- a/src/ops/op_enum.h
+++ b/src/ops/op_enum.h
@@ -177,6 +177,8 @@ typedef enum {
     E_OP_R_MIN,
     E_OP_R_MAX,
     E_OP_TOSS,
+    E_OP_WTOSS,
+    E_OP_WT,
     E_OP_MIN,
     E_OP_MAX,
     E_OP_LIM,
@@ -817,6 +819,7 @@ typedef enum {
     E_MOD_SKIP,
     E_MOD_OTHER,
     E_MOD_PROB,
+    E_MOD_PRB,
     E_MOD_DEL,
     E_MOD_DEL_X,
     E_MOD_DEL_R,